The Yale Law Journal

October 2016

The Judicial Enforceability and Legal Effects of Treaty Reservations, Understandings, and Declarations

Constitutional LawConflict of LawsInternational Law

abstract.The United States often ratifies multilateral treaties by relying on what are commonly referred to as reservations, understandings, and declarations (RUDs). RUDs limit the domestic effect of treaties and confine provisions to particular meanings consistent with the United States’ practices. In recent years, during and after the U.S. Supreme Court’s consideration of Bond v. United States, some government officials have become increasingly concerned that RUDs could be unenforceable in courts, thereby exposing the United States to unintended treaty commitments and liabilities. Remarkably, the legal literature does not contain a comprehensive account of the extent to which RUDs are enforceable in courts of law. Such an understanding may influence domestic and international perspectives on ratifying future treaties, including the pending Convention on the Rights of Persons with Disabilities and the United Nations Convention on the Law of the Sea. Consequently, this Note provides an original, searching review of the jurisprudence of RUDs in U.S. and international courts. It finds that U.S. courts and international courts consistently enforce RUDs, except for international courts reviewing treaties that expressly prohibit their use. Such findings should offer solace to those worried about the possibility that RUDs are inadequate to protect against unintended domestic effects of treaties. At the same time, they also reveal that the real concern over RUDs is not their insufficient drafting, but rather their overuse. There is a risk that treaties may increasingly prohibit RUDs, and that international courts will readily enforce these prohibitions. Given that there is no threat of the domestic invalidity of RUDs, this Note argues that the United States and other states should refrain from overusing RUDs and consequently risking broader treaty formulation and compliance.

author. Yale Law School, J.D. expected 2017. I am immensely grateful for the many gracious mentors, colleagues, family, and friends who made this Note possible. For unwavering guidance and support at every step, I thank Oona Hathaway, who led the International Law and Foreign Relations Seminar at Yale Law School where this project first took shape. For their astute advice and comments both during and after that seminar, I also thank Rebecca Crootof, as well as Emily Chertoff, Lara Domínguez, Daniel Hessel, Zak Manfredi, Julia Shu, Peter Tzeng, and Sarah Weiner. For invaluable discussions and suggestions to improve the piece, I thank Jonathan Gould, Harold Koh, W. Michael Reisman, Judith Resnik, and Edward Swaine. For their excellent editorial assistance and insightful revisions, I thank the editors of the Yale Law Journal, including in particular Sarah Burack, Hilary Ledwell, and Urja Mittal. And for their constant encouragement and inspiration along this journey, I thank my wonderful family and friends.


In 2014, as the U.S. Senate debated advice and consent to ratify the Convention on the Rights of Persons with Disabilities, the U.S. Supreme Court heard oral arguments in Bond v. United States,1 a peculiar case involving a domestic application of the International Convention on the Prohibition of the Development, Production, Stockpiling, and Use of Chemical Weapons and on Their Destruction. The Third Circuit had held that the prohibitions of the Convention, and of the accompanying Chemical Weapons Convention Implementation Act of 1998, applied to a domestic defendant who had tried to get revenge for an extramarital affair by spreading small amounts of toxic chemicals on the plaintiff’s property. Ultimately reversed by the Court later that year, the case nonetheless alarmed many who expected that the Chemical Weapons Convention could not possibly regulate local criminal activity. That the Disabilities Convention could be similarly construed was not lost on senators during hearings on that Convention.2

Bond reignited national interest in reservations, understandings, and declarations, or RUDs, despite not addressing such provisions directly. RUDs are often used by the U.S. Senate in an effort to prevent unintended consequences stemming from treaty ratification. Loosely defined, RUDs are attachments on international treaties made by a ratifying state that alter or clarify the legal effect of treaty provisions.3 In the United States, they are generally adopted by the Senate when it is giving its advice and consent to a treaty, and they must be included should the President decide to ratify the treaty. RUDs have allowed the United States to ratify treaties without assuming international obligations that might conflict with domestic obligations or otherwise place the government in a difficult legal or political position.4 Non-self-executing RUDs,5 including the one involved in Bond, keep international treaties and their standards from having domestic effects, including from being enforceable in domestic courts.6 For these reasons, the United States has both commonly and increasingly employed RUDs, as have many other states.7

The concern that treaties could have unintended domestic effects disquieted senators and other government officials who wondered to what extent they could rely on this practice for limiting the effects of treaties.8 For example, during a congressional panel on the Disabilities Convention, one senator inquired whether RUDs could be inadequate and unenforceable:

Is there a way, in your opinion, to write RUDs, on the front end of a treaty, that would absolutely ensure that there is no way for this treaty to affect either the federalism issues that we have to deal with or to cause a court to look to the treaty to actually affect the individual lives of citizens here in the country? Is there a way of us coming together and writing RUDs in that way?9

While Bond fueled these worries, shared by many senators,10 they are not new. Rather, these concerns have persisted and resurfaced many times over the last few decades as government officials questioned the judicial enforceability of RUDs.11 Whether RUDs are enforceable raises deep questions regarding the effectiveness and robustness of treatymaking and its future. Depending on their enforceability, the use of RUDs implicates the entire constitutional system of treatymaking and whether and how the United States ratifies treaties.12 And in turn, if courts will enforce RUDs, should that change how they are drafted? What are the legal effects of using certain RUDs over others?

These questions are of particular import domestically and internationally as treatymaking risks being substituted by alternatives such as congressional-executive agreements.13 As of now, treaties remain the most frequent, if not exclusive, instruments for agreements in a number of areas, including arms control, dispute settlement, and human rights.14 With them, RUDs remain central tools in the ratification process. As of June 2016, there were thirty-eight treaties pending before the Senate, including the Disabilities Convention and the United Nations Convention on the Law of the Sea (UNCLOS),15 and questions over the enforceability and effects of RUDs are paramount to whether these treaties could ultimately be ratified by the United States. Alternately, the invalidation of RUDs could be devastating. Not only would the United States face the type of domestic lawsuits presented in Bond, but it could also be forced into a variety of international disputes and into rescissions of its conditional consent.16

But so far, despite their significance, legal scholars and U.S. government officials assessing RUDs have mainly spoken past each other. Senators and presidential administrations have mostly worried about actual enforceability, while legal scholars have instead presumed that RUDs will be enforceable. These scholars often argue over the optimal level of RUD usage, and they primarily debate about whether the practice of RUDs is good law and good policy. These perspectives are important in their own right, but they are informed by and benefit from being joined together. Namely, before exploring the domestic and international effects of RUDs, and how the Senate and other government institutions could determine their optimal use, the scope of RUDs’ enforceability needs to be understood. Once that picture is clear, arguments over the proper scope of RUDs can be brought into focus.

This Note embarks on that task. It explores two major questions. First, are RUDs enforceable in courts of law? Second, if RUDs are enforceable, what is their optimal use in the treaty ratification process? To answer these questions, this Note bases both its positive and normative components on a searching analysis of case law discussing the judicial enforceability of RUDs in both U.S. and international courts.17 The analysis includes forty-seven U.S. cases discussing RUDs as a general category and twenty-six U.S. cases discussing interpretative understandings and declarations, out of approximately 650 reviewed cases. The analysis also includes fourteen cases from international courts, out of approximately 300 reviewed cases, including cases from the International Court of Justice (ICJ), the UNCLOS tribunal and arbitral bodies, the European Court of Human Rights (ECtHR), and the Inter-American Court of Human Rights.

Ultimately, this Note finds that U.S. courts and international courts consistently enforce RUDs, except for international courts reviewing treaties that expressly prohibit their use. These findings should offer solace to those worried about the inadequacies of RUDs, and they provide a compelling reason for revisiting the concerns over their use. This Note argues that based on this case law, the real concerns for the United States and other states should be the legal effects of RUDs on an international order that seeks to encourage genuine and full treaty participation, rather than their ability to mitigate unintended domestic effects. Without a viable threat to the domestic validity of RUDs, this Note reasons that the United States and other states should refrain from overusing RUDs and consequently jeopardizing broader treaty formulation and compliance.

The Note is organized in four major parts. Part I begins by providing background about the use of RUDs and traditional rationales both for and against their use. While some proponents have argued that RUDs allow for more states, including the United States, to participate in the ratification of multilateral treaties, others are more critical and argue that RUDs contribute to superficial ratifications. While legal scholars have documented the history, motivations, scope, and effects of RUDs, particularly as they relate to the Vienna Convention on the Law of Treaties (VCLT), the judicial enforceability of RUDs has not yet been comprehensively examined. The issue of enforceability is nonetheless an important piece of this normative debate because it provides a more realistic picture of what legal effects RUDs could have, if any at all.

Parts II and III take up this question about enforceability. Part II describes how, in U.S. courts, RUDs are nearly always recognized as valid. U.S. courts have only questioned the validity of RUDs when they were not properly communicated to other state parties, when their text did not support an argued interpretation, or when they focused on issues of wholly domestic concern. A few judges have published dissents arguing against the validity of RUDs, but these opinions were not controlling. Part III, in turn, describes how, with few exceptions, international courts also usually defer to RUDs. The ICJ has indicated that it can invalidate a reservation as incompatible with the object and purpose of a treaty pursuant to Article 19 of the VCLT. Yet the ICJ has only invalidated a RUD where the treaty in question expressly prohibited such a RUD. Rules stipulated by a treaty may also shape how other courts review RUDs. The ECtHR, for instance, applies treaty rules to invalidate RUDs that are of a general character or fail to include a statement of the law concerned.

Finally, Part IV draws lessons from this account of the judicial enforceability of RUDs and argues for certain treaty practices based on those lessons. First, the case analysis indicates that U.S. officials can take solace in the fact that RUDs will continue to have the force of law in domestic and international courts; every indication therefore seems to suggest that RUDs are here to stay. But some of the traditional concerns over RUDs could and should be revisited, including what RUDs signal about treaty formulation and compliance, and the risk that RUDs increasingly could be prohibited in treaties altogether. For that reason, this Note concludes that the real risk with respect to RUDs is not their insufficient drafting, but rather their overuse. Given little threat of the domestic invalidity of RUDs, the United States should not overuse RUDs and risk compromising broader treaty formulation and compliance among states.

i. background on the use of and concerns over ruds

The origins of RUDs and their important role in supporting the United States’ treaty ratification efforts date back to the early 1950s when U.S. Senator John Bricker proposed a constitutional amendment to make all treaties non-self-executing.18 When that amendment failed by one vote,19 senators turned to RUDs as an alternative means by which to ratify treaties while preserving sovereignty, federalism, and other apparent American concerns.20 The United States’ participation in human rights treaties, which only took off in the 1970s, has relied on the use of RUDs for these purposes ever since.21

But while U.S. senators have mainly sought to draft RUDs so that they will be unassailable in courts, legal scholars have mostly focused on theoretical discussions of their effects, particularly with respect to how RUDs will influence international treaty formulation and compliance.22 Some have supported the value of RUDs in allowing states, including the United States, to participate more actively in treatymaking.23 Along these lines, scholars have defended the practice of RUDs as a valid exercise of the Senate’s powers,24 and, more broadly, as a legitimate function of states that are serious about adopting treaty obligations.25 Furthermore, some scholars have suggested that RUDs may lead to more honest reflections of the positions of reserving states26 and can provide a starting point for engaging with and eventually internalizing particular norms.27

Critics meanwhile have condemned the practice of RUDs on both legal and functional grounds,28 accusing RUDs of leading to a “specious, meretricious, [and] hypocritical” process of ratification,29 through which the United States reaps the benefits of treaty participation while never assuming any obligations.30 More specifically, some have criticized RUDs as detracting from the United States’ moral commitments to human rights, including, for example, those contained in the International Covenant on Civil and Political Rights (ICCPR).31 Similarly, within the broader international community, RUDs have been criticized as abrogating the universal values and commitments signaled by human rights treaties32 and destroying any semblance of treaties as contracts.33 Furthermore, RUDs risk contravening the VCLT by violating Article 19’s prohibition against reservations that are “incompatible with the object and purpose of the treaty”34 and Article 27’s restriction on citing domestic law to avoid treaty obligations.35

Both proponents and critics of RUDs acknowledge that there is an unavoidable tradeoff between protecting the rights and consent of non-reserving states that anticipate compliance with treaties in their entirety and the rights and consent of reserving states that expect to have their RUDs honored, with the VCLT36 tilted toward protecting the rights of the latter.37 Yet before concluding where the law should stand on allowing or limiting RUDs, more needs to be known about what the law already provides about their enforceability. This is after all the major concern of senators deciding whether to ratify treaties with RUDs. In other words, whether RUDs are already limited in courts of law is a practical reality that has demanded the attention of government officials and should inform any normative consideration of their use.

Remarkably, the legal literature does not contain a comprehensive answer to the persistent questions over the judicial enforceability of RUDs. In the limited instances where the issue has been considered, RUDs have generally been summarily presumed to be valid in courts of law.38 The positive account of RUDs has focused on exploring their possible rules and limitations based on the VCLT’s provisions on reservations or on the effect of one state’s objections on another state’s RUD.39 Several early works were devoted to studying the history, motivations, scope, and effects of RUDs across states and treaties, particularly by comparing and connecting them to the principles set forth in the VCLT.40 Others have explored how parties should be bound if RUDs are invalidated.41 But scholars studying these VCLT provisions and the broader law surrounding RUDs, which many consider to be unclear,42 do not provide consistent guidance as to how courts will treat RUDs. Additionally, the United States has not ratified the VCLT, and except among scholars who consider the VCLT customary international law, it is not clear if the VCLT binds the United States.43

As the Introduction suggests, an account of the depth and breadth of this enforceability is all the more pressing as it may influence the likelihood that the United States will ratify further treaties. More broadly, such an account may address the longstanding concerns of senators and other government officials and allow them to engage more fully with the question of the optimal scope of RUDs that has long been the focus of legal scholars. This Note endeavors to fill this gap by providing an original and searching account of how courts enforce, and do not enforce, RUDs.

ii. the enforceability of ruds in u.s. courts

Article II of the Constitution governs the treatymaking process in the United States.44 This process generally begins with the President’s administration negotiating the terms of a treaty with foreign states, followed by a signature and transmission to the Senate for its advice and consent.45 The Senate can provide its advice and consent by approving the treaty through a two-thirds vote and a resolution sending the treaty back to the President, or it can keep the treaty pending. As part of its advice and consent, the Senate can condition its approval by adopting RUDs in its approving resolution. The President can then either choose to ratify the treaty with the RUDs becoming a part of the United States’ agreement46 or refuse to ratify the treaty altogether.47 It is largely understood among states that in bilateral treaties, consent to the RUDs by the other state party is required before the RUDs can go into effect; in multilateral treaties, consent by each state party is generally not required unless the treaty appears to require it.48

While RUDs can take many forms, they can generally be characterized in one of three ways.49 Reservations qualify U.S. obligations without necessarily changing the treaty’s text.50 They are often used to except the United States from certain problematic treaty provisions, to avoid conflicts between treaty provisions and the U.S. Constitution, or to escape obligations where there are political or policy disagreements.51 Meanwhile, understandings clarify or elaborate provisions but do not change them.52 They are used to explain the United States’ interpretation of certain treaty terms and to clarify its consent to a particular provision.53 Finally, declarations express the Senate’s position on matters relating to issues raised by the treaty as a whole.54 A common declaration is one that declares the treaty to be non-self-executing or nonenforceable in U.S. courts as long as there is no implementing domestic legislation.55

For example, the Senate provided its advice and consent for the ICCPR while adopting several RUDs, including the following:

a reservation that “the United States reserves the right, subject to its Constitutional constraints, to impose capital punishment on any person (other than a pregnant woman) duly convicted under existing or future laws, permitting the imposition of capital punishment, including such punishment for crimes committed by persons below eighteen years of age”;56

an understanding that the “Covenant shall be implemented by the Federal Government to the extent that it exercises legislative and judicial jurisdiction over the matters covered therein, and otherwise by the state and local governments; to the extent that state and local governments exercise jurisdiction over such matters, the Federal Government shall take measures appropriate to the Federal system to the end that the competent authorities of the state or local governments may take appropriate measures for the fulfillment of the Covenant”;57 and

a declaration that “the provisions of Articles 1 through 27 of the Covenant are not self-executing.”58

According to a quantitative analysis of RUDs documenting 200 years of the United States’ treatymaking up until 1996, the United States entered into 1,286 treaties pursuant to Article II, including 195 (or fifteen percent) with RUDs adopted during the Senate’s advice and consent process.59 A more recent analysis reviewing 400 multilateral treaties ratified between 1960 and 2009 suggests that the United States’ use of RUDs has increased and continues to increase over time.60 But even while RUDs have become a standard feature of modern treatymaking practice, their actual enforceability in courts has largely been presumed. Scholars have not looked in depth into the range of court cases reviewing the use of RUDs.

In this Part, I analyze U.S. case law to determine the enforceability of RUDs in U.S. courts. To construct a comprehensive set of U.S. court cases directly engaging with the enforceability of RUDs, I conducted a search for all federal cases containing the term “RUDs” (a common term in public international law and among courts), which returned twenty-seven cases. I then conducted a second search using the search string “reservations, understandings, and declarations,” which returned 393 cases, which, upon review, included twenty unique cases that engaged with the question of the legal validity of RUDs. To capture cases that may not refer to this grouping, I conducted a third search using a more general search string in order to locate interpretative understandings and declarations and reviewed the most relevant 250 cases returned.61

The remainder of this Part describes the prevailing view in U.S. case law that RUDs are valid and enforceable in U.S. courts. It then discusses the few instances in which the validity of RUDs has been questioned.

A. Valid and Enforceable RUDs in U.S. Courts

In the cases reviewed, U.S. courts consistently recognize the validity and enforceability of RUDs and consider them to be legally binding as a condition of the Senate’s advice and consent.62 If the Senate conditions its approval of a treaty upon certain RUDs, the President can ratify the treaty only with those RUDs. This has been the longtime understanding of the constitutional arrangement.63

1. U.S. Supreme Court Case Law

The U.S. Supreme Court has never expressly ruled on the validity of RUDs, but it has implicitly recognized their validity by enforcing them in a number of cases. Most prominently, in Sosa v. Alvarez-Machain, a Mexican national sued the Drug Enforcement Administration for an arbitrary arrest.64 Among several claims, the plaintiff argued that the arrest violated his rights under Article 9 of the ICCPR.65 The Court recognized the ICCPR’s non-self-executing declaration as dispositive for rejecting that claim, explaining that the Senate granted its advice and consent to the ICCPR with a reservation providing that the treaty “was not self-executing and so did not itself create obligations enforceable in the federal courts.”66

Expressly recognizing the existence of RUDs, the Court observed that “[s]everal times . . . the Senate has expressly declined to give the federal courts the task of interpreting and applying international human rights law, as when its ratification of the [ICCPR] declared that the substantive provisions of the document were not self-executing.”67 Furthermore, the Court held that although the United States was bound by the ICCPR, “the United States ratified the Covenant on the express understanding that it was not self-executing and so did not itself create obligations enforceable in the federal courts.”68 The Court denied the argument that the Universal Declaration of Human Rights and the ICCPR could themselves constitute the relevant and applicable rules of international law.69 While not commenting on the validity and enforceability of RUDs in general, the Court recognized a specific non-self-executing declaration, a reservation with arguably some of the most significant legal effects among RUDs,70 as valid and enforceable.

The Court has also weighed in at least twice on interpretative understandings and declarations, although apparently only in cases concerning bilateral treaties. In 1853, the Court held in Doe v. Braden that written declarations interpreting ambiguous language that are then ratified by the other party become a part of the treaty and are therefore obligatory.71 Almost a century later, the Court recognized a declaration “providing that nothing in the treaty should be construed to” have any meaning beyond what the qualification specified.72 Although the Court referred to the declaration as an amendment, the language suggests that the qualifier was in fact a RUD.73 These two cases provide the most persuasive authority that interpretative understandings and declarations constitute a part of the treaty and should therefore be enforced as part of the treaty obligation, at least insofar as the RUD has received bilateral assent.

2. District and Circuit Court Case Law

Following the Supreme Court’s guidance in Sosa, lower courts have consistently upheld RUDs, often in even more direct terms. For example, lower courts have repeatedly upheld reservations and declarations stating that certain treaties or treaty provisions are non-self-executing, most prominently in cases involving the ICCPR.74 In Igartúa v. United States, for instance, the First Circuit expressly recited the holding in Sosa that recognized the ICCPR as non-self-executing given the Senate’s condition at the time of advice and consent.75 The Second Circuit was even more explicit, denying a claim under the ICCPR by reasoning that “[t]he only ratified treaty cited . . . by [the plaintiff], the ICCPR, came with attached RUDs declaring that the ICCPR is not self-executing. This declaration means that the provisions of the ICCPR do not create a private right of action nor separate form of relief enforceable in United States courts.”76 In addition to enforcing the non-self-executing declaration, lower courts have consistently upheld the reservation to the ICCPR that retains the right of the United States to impose capital punishment on juveniles under eighteen years of age, even though the ICCPR prohibits this practice.77

With regard to interpretative understandings and declarations, most case law comes from interpretations of the U.N. Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (CAT), which has been implicated indirectly through litigation under the Foreign Affairs Reform and Restructuring Act of 1998 (FARRA).78 In Auguste v. Ridge, the Third Circuit applied the United States’ “understanding” that torture must include a specific intent element.79 The Second Circuit cited Auguste in reaching the same conclusion two years later.80 The Ninth Circuit has similarly upheld interpretations of Article 3’s “substantial grounds for believing that he would be in danger,” which is the risk threshold above which a state cannot force refugees or asylum seekers to return to the country they fled, to mean “if it is more likely than not that he would be tortured.”81 Such a definition is critical for determining whether a state has a legal obligation not to deport certain refugees or asylum seekers. While in each of these cases the courts were applying FARRA, the courts’ unquestioning treatment of the CAT’s understandings as legally dispositive of FARRA’s meaning suggests that the CAT’s understandings are indeed valid.

Courts interpreting and enforcing other prominent multilateral treaties have also cited interpretative understandings and declarations in their decisions. Most of these cases do not expressly rely on the RUDs in their ultimate holdings, but a few have. The U.S. District Court for the Eastern District of New York, for example, held that the use of herbicides did not constitute genocide in part by referring to the U.S. interpretative understanding that specific intent is required for genocide to be committed under the Genocide Convention.82 Similarly, in 1928, the U.S. District Court for the District of Maryland recognized that an interpretative understanding did not have to be a reservation to be binding.83 The court found that bilateral assent to the interpretative understanding was sufficient.84 The court did not discuss what would happen if the interpretative understanding was only a unilateral understanding, as discussed next.

B. Limitations of the Enforceability of RUDs in U.S. Courts

RUDs are therefore almost always enforced by U.S. courts. But there have been a few discrete instances in which courts have questioned their use in specific contexts. The significance of these few cases should not be overstated, however, given that none of these cases invalidated a recognized RUD. The only opinions not giving effect to a RUD occurred where (1) the treaty condition was never communicated to other treaty parties or (2) the reservation only addressed matters of domestic concern (although the case on this point is not binding precedent, as it was vacated on other grounds). Two judges on the First Circuit have questioned the validity of RUDs practice as a whole, but only in dissenting opinions.

First, lower courts have raised questions about treaty conditions that were not communicated to other parties and about subsequent interpretations not supported by the treaty’s text. For instance, the Federal Circuit and the Court of Federal Claims both reasoned in separate decisions that a “Technical Explanation” in a treaty could not be controlling where it appeared that only the United States had been privy to the documents.85 Furthermore, the Court of Federal Claims determined that it was unlikely that “at the time of Treaty ratification” the United States contemplated the situation that had since occurred.86 It therefore found that the government’s proposed interpretation could not be read into the treaty, thereby in effect finding the purported RUD invalid and unenforceable.87

Second, in Power Authority v. Federal Power Commission, the D.C. Circuit reviewed a purported RUD attached to a treaty with Canada.88 In that RUD, the United States reserved the right to develop its share of the Niagara River through an act of Congress and prohibited redevelopment projects until otherwise authorized through congressional enactment.89 The court did not give effect to the reservation, holding that a reservation needed to reach an issue of international concern.90 The Supreme Court ultimately vacated the judgment, remanding the decision “with directions to dismiss the petition on the ground that the cause is moot.”91 The D.C. Circuit’s decision is therefore not valid precedent, and other courts have not since followed its logic. However, though vacated, Power Authority mayprovide insight into the potential skepticism of courts toward a reservation that does not pertain to relations with other states or that otherwise alters the effect of the treaty with regard to any other party.92 The D.C. Circuit held that, in such instances, what appeared to be a reservation was not in fact a formal reservation, given that it addressed issues of wholly domestic concern.93

Finally, in Igartúa-de la Rosa v. United States,94 two dissenting judges argued that RUDs ought to be invalidated in light of the Supremacy Clause, which expressly establishes the priority of the Constitution, federal laws, and treaties made under the “Authority of the United States” over other laws and legal instruments.95 Judge Torruella wrote, “[T]he United States is not in compliance with the binding obligations it undertook by signing and ratifying the ICCPR. The majority does not and cannot refute this undeniable fact, and . . . the potentially non-self-executing nature of the ICCPR does not preclude our ability to make a declaration to that effect . . . .”96 Therefore, Judge Torruella would have found that the United States’ commitment to the treaty, as a supreme law, takes priority over any reservation withholding obligations under the treaty.

Also dissenting, Judge Howard wrote that “separation of powers considerations prevent a court from relying exclusively on the Senate’s declaration . . . . The Supremacy Clause and Article III require a court to examine independently the intentions of the treatymakers to decide if a treaty, by its own force, creates individually enforceable rights.”97 Judge Torruella expressed the same viewpoint again five years later.98

These continue to be minority viewpoints and have not been endorsed in any binding decision by the First Circuit or any other U.S. court. Overall, the isolation of these views in the case law indicates the robustness of RUDs in U.S. courts. RUDs today are made public and communicated to other parties. Neither Power Authority nor the dissenting opinions in the First Circuit constitute binding law. The cases reviewed in this Section are therefore the exceptions, rather than the rule. U.S. courts can be expected to treat RUDs as valid and enforceable.

iii. the enforceability of ruds in international courts

The equivalents of RUDs, which are primarily discussed as a conglomerate in U.S. contexts, in international law are reservations and interpretative declarations. The International Law Commission’s (ILC) Guide to Practice on Reservations to Treaties provides helpful definitions that parallel those previously discussed in Part II. It defines a reservation as

a unilateral statement . . . made by a State or an international organization when signing, ratifying, formally confirming, accepting, approving or acceding to a treaty, or by a State when making a notification of succession to a treaty, whereby the State or organization purports to exclude or to modify the legal effect of certain provisions of the treaty in their application to that State or to that international organization.99

Meanwhile, an interpretative declaration is a unilateral statement “made by a State or an international organization, whereby that State or that organization purports to specify or clarify the meaning or scope of a treaty or of certain of its provisions.”100

For the purposes of distinguishing between these types, whether a statement is formally titled a reservation or a declaration is less important than how it operates. According to the ILC, “[t]he character of a unilateral statement as a reservation or as an interpretative declaration is determined by the legal effect that its author purports to produce,” which should be determined by interpreting the statement “in good faith in accordance with the ordinary meaning to be given to its terms, with a view to identifying therefrom the intention of its author, in light of the treaty to which it refers.”101 Moreover, the abstract definitions might not prove particularly helpful, given that the guidance essentially involves a circular logic distinguishing the two terms using their own definitions.

In this Part, I analyze international case law to determine the judicial enforceability of RUDs, namely reservations and interpretative declarations, in international courts. To locate international cases engaging with RUDs, I conducted searches using terms including “reservations,” “declarations,” and “interpretative declarations.”102 In total, approximately two dozen cases out of 300 cases reviewed were found to be relevant, and fourteen of those directly engaged with the question of RUDs.103 I considered advisory opinions where the principles discussed were directly relevant to RUDs, but I focused largely on judgments given their binding authority.104

The international case law demonstrates that courts have also generally enforced RUDs. At the same time, international courts have warned that RUDs could be invalidated where they fail the VCLT’s “object and purpose” test, and these courts have stopped short of enforcing certain RUDs where the relevant treaties expressly limited their use. The ICJ cases, which are arguably most prominent in discussing reservations and interpretative declarations, are discussed first, followed by cases from other international courts. Court decisions that directly engaged with the question of RUDs were included in the case review, although any case that involved RUDs was considered in the analysis. This Part concludes with a discussion of the legal effect of objections by treaty parties to RUDs adopted by other parties.

A. International Court of Justice (ICJ) Jurisprudence

According to Article 19 of the VCLT, reservations to treaties are permissible with a few exceptions:

A State may, when signing, ratifying, accepting, approving or acceding to a treaty, formulate a reservation unless: (a) [t]he reservation is prohibited by the treaty; (b) [t]he treaty provides that only specified reservations, which do not include the reservation in question, may be made; or (c) . . . the reservation is incompatible with the object and purpose of the treaty.105

The first two exceptions apply to specific treaty provisions, while the third is generally applicable to all treaties and involves a court determination.106 Applying the third exception, international courts typically ask whether reservations to treaties, where otherwise not prohibited, are compatible “with the object and purpose of the treaty.”107 If the reservation is compatible, it is presumably valid and should be upheld, and if it is not compatible, the reservation violates Article 19 and is presumably invalid.

ICJ’s early advisory opinion on reservations to the Genocide Convention adopted this “object and purpose” compatibility test for determining the validity of RUDs and established procedures for objections that would later be codified in the VCLT.108 Since that opinion, the ICJ has established a number of principles on RUDs through binding judgments. In Fisheries Jurisdiction, the ICJ explained that it will interpret a reservation in a “natural and reasonable” way with regard to the intention of the reserving state when it ratified the treaty.109 In Border and Transborder Armed Actions, the ICJ illustrated that a reservation can be distinguished from an interpretative declaration. In that case, the ICJ cited a U.S. reservation to the Pact of Bogotá limiting the ICJ’s jurisdiction as an indication that the Pact otherwise gave the court compulsory jurisdiction over the case.110 Honduras, arguing that the Pact did not provide for compulsory jurisdiction, attempted to suggest that the U.S. reservation was merely an interpretative declaration and not reflective of the Pact’s legal effect absent the alleged declaration.111 The ICJ disagreed, holding that the United States’ express limitation on the court’s jurisdiction was intended as a reservation, was valid, and served as an indication that jurisdiction was otherwise compulsory.112 The ICJ has since applied the object and purpose test to uphold a number of reservations limiting jurisdiction of the court under the Genocide Convention. In Armed Activities, the ICJ held that Rwanda could make a reservation to Article IX of the Genocide Convention limiting the ICJ’s jurisdiction.113 The ICJ relied on two preceding cases, Yugoslavia v. Spain and Yugoslavia v. United States, in which the court had held as valid similar reservations by Spain and the United States.114

While these holdings provide robust case law on the validity and enforceability of reservations within the ICJ’s jurisprudence, some judges within the court have argued in dissents that reservations that are compatible with the object and purpose of a treaty may nonetheless be invalidated for other reasons. In his dissent to Armed Activities, for example, Judge Koroma argued that reservations that are incompatible with the raison d’être of a treaty should be invalid.115 Similarly, in Yugoslavia v. United States, Judge Kreća dissented to argue that jus cogens norms can and must override inconsistent reservations.116 Judge Kreća clarified that he believed no difference exists between reservations and understandings in such an inquiry.117

Generally, the ICJ has found that interpretative declarations are also valid, at least to the extent they were agreed upon by the other parties to the treaty. In the Ambatielos Case, the ICJ recognized an interpretative declaration as binding.118 The court reasoned that it could be understood either by the instrument of ratification or by necessary implication that the declaration must be considered provisions of the treaty.119 Judge Carneiro, writing an individual opinion in that case, referred explicitly to the declaration as an interpretative declaration and explained that it was a binding component of the treaty.120

But one other case suggests that interpretative declarations can be challenged, at least when they act as reservations and are prohibited by treaties. In Maritime Delimitation in the Black Sea, the ICJ cast aside an interpretative declaration.121 In that case, the ICJ was asked to consider a RUD adopted by Romania when it ratified the United Nations Convention on the Law of the Sea (UNCLOS), a treaty that prohibits most reservations but allows certain interpretative declarations as long as they do not purport to exclude or modify the legal effect of the convention.122 Romania had issued an interpretative declaration regarding Article 121,123 which establishes the definition of an island as “a naturally formed area of land, surrounded by water, which is above water at high tide” and distinguishes rocks that cannot sustain human habitation or economic life of their own in Article 121(3) as not having an exclusive economic zone or continental shelf.124 The interpretative declaration allowed for a more preferable delimiting boundary by not considering rocks as part of the delimitation of maritime spaces. In a highly unfavorable decision for Romania, the ICJ held that the declaration could not modify the legal effect of the UNCLOS provisions.125

At work in Black Sea and the invalidation of the alleged interpretative declaration were two related provisions of UNCLOS: a prohibition on reservations unless expressly permitted elsewhere in the treaty and the allowance of declarations or statements as long as they do not exclude or modify the legal effect of UNCLOS’s provisions. It can be inferred that the latter provision ensures that interpretative declarations will not simply masquerade as reservations; in this instance, the ICJ explicitly relied on the latter in dismissing Romania’s declaration, plausibly doing so because it regarded the interpretative declaration as an effort to evade that treaty’s prohibition on reservations. In any case, while interpretative declarations might be subject to greater scrutiny for enforceability than reservations, the Ambatielos Case is likely to be more representative of the legal effect of interpretative declarations when they are not otherwise limited. But Black Sea stands for the important principle that a treaty can restrict reservations and interpretative declarations and thereby make them unenforceable in international courts.

B. Other International Court Jurisprudence

With a few limited exceptions, other international courts have also found reservations to be valid. But again, in a similar vein to Black Sea, courts make exceptions when treaties include express limitations against certain types of reservations. The various human rights courts, for instance, provide insight into the use of reservations and declarations under the authority of specific human rights treaties with particular requirements.126 In the case law of these courts, reservations that appear to violate the internal rules of the relevant treaty, as well as understandings and declarations that appear to sidestep these limitations, are invalidated and rendered unenforceable. For example, consistent with Black Sea, an arbitral tribunal held that a Russian declaration excluding certain disputes from court jurisdiction could be recognized but was limited by the treaty’s express description of which declarations would be permissible.127

The European Court of Human Rights (ECtHR), a court with particularly express case law in this area, has invalidated reservations that do not conform to the requirements of the European Convention on Human Rights (ECHR). Article 64 of the ECHR prohibits “[r]eservations of a general character” and requires “a brief statement of the law concerned” for any reservation.128 The ECtHR Grand Chamber explained that the Article limits the ability of States to make reservations excluding areas of law from supervision by “Convention institutions,” explaining that such prohibitions are necessary to ensure equality and unity among parties to maintain and recognize human rights.129 Relying on this Article, the ECtHR has invalidated two Swiss reservations: one for not conforming to the requirement to append a brief statement of the law concerned,130 and one about the meaning of a fair trial for being a reservation of a general character.131 In both cases, the ECtHR held that Switzerland was still bound to the Convention.

Meanwhile, the Inter-American Court of Human Rights (IACtHR) conducts a similar inquiry examining whether challenged reservations are compatible with the American Convention on Human Rights, which allows reservations that are in conformity with the VCLT.132 Accordingly, the IACtHR has invalidated reservations deemed to be incompatible with the Convention, although its inquiry appears to be less searching than ECtHR’s review.133 Scrutinized reservations appear to be those that are “general in scope, which completely subordinate[] the application of the American Convention to the internal legislation of [a state] as decided by its courts.”134 When assessing a reservation, the IACtHR has determined the reservation’s meaning based on its text, even when a state argues for a different understanding.135 The ECtHR and IACtHR have therefore endorsed the principle that treaties may place express limitations on reservations and interpretative declarations, thereby invalidating them at least when challenged before the specific courts tasked with enforcing those conventions.

C. Formal Objections by a State to Another State’s RUDs

Although not prominent in the case law, understanding RUDs in an international context also benefits from a brief mention of formal objections by a state to another state’s RUDs. In addition to establishing rules on when RUDs are permissible, the VCLT provides procedures for these objections. Article 20 establishes that, under certain conditions, consent by all parties to a given reservation is not always required for a treaty to enter into force, such as when the treaty expressly authorizes reservations. It notes that “[a] reservation expressly authorized by a treaty does not require any subsequent acceptance by the other contracting States unless the treaty so provides.”136 Furthermore, there is generally a twelve-month period for objecting to a reservation, after which other parties’ tacit acceptance to a reservation will be assumed.137 Article 21 lays out the conditions under which reservations and objections to reservations will have legal effect. When a state objects to another state’s reservation but otherwise does not object to the treaty entering into force, the provisions to which the reservation relates will not apply between the two State parties to the extent of the reservation.138

While rare, states do object to other states’ reservations. A small but not insignificant number of states have objected to U.S. reservations to multilateral treaties, including objections from three states to U.S. reservations to the CAT.139 The Netherlands, for instance, objected to the U.S. reservation to Article 16 of the CAT as incompatible with the CAT’s object and purpose and to the U.S. interpretation of “torture” under Article 1 as invalid.140 Similarly, eleven states objected to U.S. reservations to the ICCPR.141 Germany, for instance, objected to the U.S. reservation to Article 6, which allows capital punishment for those under the age of eighteen.142

There is no indication in the reviewed case law that any U.S. or international court has ever cited a documented objection by another state as a dispositive factor in invalidating a RUD. Litigants have raised other states’ objections to U.S. RUDs in U.S. courts,143 but these objections have not been treated as a basis for rejecting a RUD. The issue has not arisen for the United States in the international court cases reviewed, leaving unsettled exactly how much legal force these objections have.

iv. revisiting the use of and concerns over ruds

The case analysis presented in these preceding two Parts offers an important point of reference to the recurring debate and concerns introduced at the outset of this Note: RUDs are usually held to be valid and enforceable in courts of law. They are likely only to be vulnerable when international courts consider treaties that limit their use. These findings suggest that the dominant concern in United States treatymaking over the domestic legal effects of RUDs is in fact misguided. The overwhelming attention that has been paid to ensuring that RUDs will be enforceable to prevent unintended domestic consequences should instead be devoted to concerns over the international effects, ones that this case analysis suggests are rooted in preventing RUDs that undermine treaty obligations. Granted, the robustness of RUDs in U.S. courts indicates that they are not going anywhere any time soon; if they are enforceable, there is little reason to think that the United States, or other states, will stop using them. But these findings encourage reorienting the concerns over the effects of using RUDs and determining their optimal scope in the treatymaking process.

More specifically, both legal scholars and government officials can now address one another’s concerns with the added benefit of a better understanding of actual RUDs enforceability, as provided by this Note’s case analysis. As this Part argues, legal scholars should consider and address the concerns over domestic legal effects of RUDs that the U.S. government has raised, as this case analysis attempted to initiate, and the U.S. government should consider the real concerns that legal scholars have raised about the international effects, informed by their consistent enforceability in domestic courts and the limited exceptions to enforceability in international courts. Section IV.A encourages recasting the U.S. perspective and priorities on RUDs, namely to focus on the international instead of the domestic effects of these instruments, and Section IV.B presents recommendations based on this reorientation.

A. Recasting the U.S. Perspective and Priorities on RUDs

In light of the preceding case analysis, U.S. senators and other government officials should take solace in the fact that RUDs have and will most likely continue to have the force of law, at least in U.S. courts and in most instances in international courts. If RUDs are enforceable, the United States and other states have little reason to stop using them. But that fact alone should not discourage those who are skeptical about the extensive use of RUDs. Rather, it is this awareness of the robust enforceability of RUDs that encourages a reexamination of the optimal scope of RUDs. The question is no longer whether RUDs are enforceable, but rather when RUDs are adopted, what is their ideal usage?

More specifically, the questions raised by senators over the Disabilities Convention should be reformulated. Rather than question whether RUDs can be drafted to insulate the United States from certain treaty obligations—they can, and they do—we should ask whether RUDs will be sustainable in a treatymaking system that is increasingly wary of treaty ratification using RUDs. The effects of RUDs usage are both domestic and international, and yet they have not been considered in detail. This Section begins by exploring the domestic effects of RUDs’ enforceability and then pivots to the international effects, namely their undermining of the treatymaking process and the possible risk of the proliferation of no-reservation treaty provisions.

1. Reorienting from the Domestic Effects of RUDs

U.S. senators have long been concerned about the possibility that treaty ratification could create domestic responsibilities and liabilities that impinge on the United States’ sovereignty and ability to determine its own obligations through domestic legislation. To that end, the use of RUDs to promote treaty ratification has been significant, especially in multilateral treaties, such as the various international human rights treaties that have been considered in the post-World War II era. In the 1950s, Senator Bricker proposed a constitutional amendment that would make “[a] treaty . . . effective in the United States only through legislation which would be valid in the absence of [a] treaty,” effectively placing a permanent RUD on all treaties that would render every one of them non-self-executing.144 The amendment eventually failed, but not without a significant cost to treaty ratification: acquiescing to the political forces backing the Bricker Amendment, the Eisenhower Administration essentially pledged to steer the United States away from human rights treaties.145 Since then, the most prominent multilateral treaties, including the CAT and the ICCPR, have only been ratified through RUDs, including non-self-executing declarations akin to that proposed in Senator Bricker’s amendment.

The United States did not always focus exclusively on unintended domestic effects. For instance, when the Senate debated ratification of the Genocide Convention in the 1980s, some senators challenged a reservation that recognized the supremacy of the Constitution. The senators noted that there was no evidence that the Convention would conflict with the Constitution, that the Constitution in any case would be supreme over a treaty, that it was “disturbing to our allies who have undertaken an unqualified acceptance of the treaty’s obligations,” and that the “self-serving nature of the reservation suggested that the United States ‘was not ratifying the . . . Convention in good faith.’”146 The senators concluded:

[The] reservation . . . will seriously compromise the political and moral prestige the United States can otherwise attain in the world community by unqualified ratification of the Genocide Convention. It will hand our adversaries a propaganda tool to use against the United States and invite other nations to attach similar self-judging reservations that could be used to undermine treaty commitments.147

Notwithstanding this criticism, the reservation ultimately passed the Senate by a vote of 83-11 on February 19, 1986.148

This focus on the international effects of RUDs has not won out. Since that contentious battle, the concerns over the possible unintended domestic effects of treaty ratification without RUDs continue to overshadow the concerns over their international effects. As the various ratified and non-ratified treaties discussed here illustrate, the United States has mostly confined itself to one of two approaches: (1) ratify a treaty with RUDs or (2) not ratify treaties at all. Neither is objectively preferable.149

Indeed, if one extreme is using RUDs for a much more conditional, arguably substance-less ratification, and the other extreme is restricting the practice of RUDs and inevitably limiting participation in multilateral treaties altogether,150 the United States has been at both extremes but rarely between them. Fueling the United States’ practices at the extremes appears to be a general lack of any real consideration of the effect that RUDs would have on the United States’ relations with other states and the wider international community. Senators have mostly concerned themselves with whether the treaty would have the domestic implications they seek (e.g., will the RUD be enforced?), thereby forgoing an analysis of the costs and benefits of using RUDs (e.g., could the United States be hindering commitments to human rights by providing such detached, conditional consent to international treaties?).

But this Note’s case analysis suggests that the United States should be operating in the middle. Concerns over the unintended domestic effects of treaties are exaggerated. Domestic courts will enforce RUDs. They have done so consistently over the years, and there is no indication that they will cease to do so. The United States government should therefore be concerned with the international implications of placing reservations on treaty provisions, both for the sake of international appearance and the effects on the behavior of other states. It should consider the international court jurisprudence, which might shape the contours of treaty enforcement in international law. Moreover, the United States should take into account how the drafting of treaties could be changing over time.

2. Reorienting Toward the International Effects of RUDs

In short, the more pressing concerns are the international effects of RUDs. Indeed, while certainly not the only country to use RUDs,151 the United States has been the target of intense criticism from the international community for its use of RUDs, particularly in human rights treaties.152 Again, a generous reading of the United States’ use of RUDs is that the United States aims for authenticity in its treatymaking process by only ratifying treaties in forms in which the United States would actually abide by them, while a less generous reading argues that the RUDs are a sign of arrogance.153 Some scholars suspect the latter to be more likely.154 The reality, accepted even by proponents of RUDs, is that RUDs at the very least influence perceptions that can have significant consequences in international relations.155 States may face backlash for their practices, and the aspiration of securing an international order that respects treaty commitments may falter.

Indeed, various international movements have arisen out of frustration with the United States and other states’ practices of using RUDs. One prominent example is General Comment 24, which was promulgated by the United Nations Human Rights Committee (UNHRC) in 1994.156 Recognizing that forty-six states had entered 150 reservations to the ICCPR, the UNHRC expressed concern that the reservations’ “content and their scope may undermine the effective implementation of the Covenant and tend to weaken respect for the obligations of States parties.”157 In that comment and thereafter, the UNHRC assumed a duty to determine whether specific reservations to the ICCPR are permissible by reviewing them under the VCLT’s “object and purpose” test. While the comment was a forceful reaction to RUDs, the UNHRC does not have any enforcement authority for its decisions and therefore can only have a limited impact in curtailing the use of RUDs.158

A more direct, potentially fomenting international movement suggested by the case analysis is a pattern of treaty drafters expressly banning RUDs in part or altogether. While scholars have rarely discussed them,159 no-reservation clauses—and related treaty provisions limiting RUDs—first appeared on the U.S. Senate’s radar decades ago.160 Over the years, they elicited concerns in the United States,161 particularly in the area of environmental treaties,162 but they have mostly been underestimated. In the 1990s, three environmental treaties—the Basel Convention, the Environmental Protocol to the Antarctic Treaty, and the United Nations Framework Convention on Climate Change—all prohibited reservations, eliciting concerns from members of the Senate.163 Senators who provided advice and consent for these treaties emphasized their concern over no-reservation clauses,164 and they clarified that their approval should not be construed as precedent for consenting to such clauses in future agreements.165 If more treaties feature these no-reservation clauses, these past events suggest that the United States will increasingly find it difficult to sign onto other treaties, even those it finds particularly important.

And it does appear that more treaties are featuring these no-reservation clauses.166 The Statute of the International Criminal Court, Comprehensive Nuclear-Test-Ban Treaty, Chemical Weapons Convention, and Anti-Personnel Mines Convention, along with a number of environmental treaties, including the Montreal Protocol, Kyoto Protocol, Rotterdam Convention, Stockholm Convention, and Cartagena Protocol, all ban reservations.167 Indeed, more recent treaties may be drafted using the language in UNCLOS, such as the Rome Statute of the International Criminal Court and the World Health Organization’s proposed Framework Convention for Tobacco Control.168 Some have explained that no-reservation clauses, including for UNCLOS, are meant to protect “package deals” where there are so many compromises that any reservation on particular clauses or the entire treaty could unhinge the agreement.169 Since they are written into the treaties themselves, they very well might take precedent over a RUD, as Black Sea and the cases from the ECtHR and IACtHR suggest. Indeed, one of the reasons the United States has not ratified UNCLOS is because of the provisions on deep seabed mining that could not be avoided through the use of RUDs.170

What could this portend for the United States? If states begin to find the United States’ use of RUDs in important treaties more inappropriate and its ratification less important, treaty drafters may be more likely to pass no-reservation provisions that limit the use of RUDs, thereby leaving the United States behind in the treatymaking process. In other words, if the United States unnecessarily concerns itself with the enforceability of its RUDs, other members of the international community could meanwhile continue to design RUDs-limiting treaties that risk foreclosing U.S. participation. Indeed, even as the United States ratifies fewer treaties, other states continue to sign and ratify contemporary multilateral treaties, with UNCLOS (168 parties)171 and the Disabilities Convention (167 parties)172 among them.

Scholars and government officials have downplayed these concerns in a variety of ways. One common response is that many of these concerns of outward appearance are exaggerated because the United States helps draft treaties and already ends up following the general framework of many treaties even if it decides not to ratify them.173 There is indeed a significant debate over whether treaty ratification makes a difference in compliance and whether other methods may be more effective in leading to change.174 Regardless of where one stands on the efficacy of the treaty regime as a whole, the reality is that key areas of international law remain solely under the purview of treaties, and the United States has shown enough interest to continue treaty deliberations for many treaties. Its dance around certain treaties and their provisions at the ratification stage therefore undermines what appears to be its supposedly genuine commitment to many treaties’ principles. The robust domestic court jurisprudence discussed here indicates that this dance is unnecessary and self-defeating. Because the United States will in almost all circumstances be bound insofar as it intends to be for any ratified treaty, the benefits of formally joining the international community in supporting the treaty’s principles it already aims to follow is likely to outweigh the costs of not doing so.

Another response is that no-reservation clauses and their potential to be enforced in international courts are irrelevant because the United States is not beholden to the judgments of international courts. Indeed, the United States has continued to refuse the compulsory jurisdiction of international courts, including the ICJ,175 and any change to this trajectory does not appear to be forthcoming.176 But not recognizing the jurisdiction of international courts does not absolve the United States from considering how those court decisions may influence the actions and positions of other states and treaty drafters. Furthermore, these international court decisions may also increasingly be considered or reflect customary international law, including decisions relating to the scope and expectations of the VCLT. If the United States cannot act within the bounds of accepted international law when ratifying treaties, its stature in the fields of arms control, human rights, and other areas relying upon multilateral treaties risks being diminished.

In short, rather than invite backlash from the international community, and even apart from the many other possible benefits of supporting a robust international order of treatymaking, the United States can and should aspire toward more substantive participation in the ratification process. This shift is especially imperative given the lack of any significant domestic tradeoffs. Whether the United States can continue to hold off from multilateral treaties without risking unwanted exclusion is simply an unnecessary gamble. The United States would be wise to limit its RUDs to the extent they are absolutely necessary and to otherwise avoid their overuse given that there are few upsides for any alternative. The next Section elaborates on these recommendations.

B. Navigating the Effects of RUDs by Limiting Their Overuse

Considering an optimal use of RUDs is an important step to ensuring their sustainability and effectiveness. Members of the ILC, for instance, have continued to debate how RUDs should be addressed,177 including by publishing a guide explaining reservations in 2011.178 The guide was drafted with the intention of assisting practitioners and therefore consists of nonbinding recommendations rather than peremptory norms.179 Like the ILC, the United States should take these concerns into account and develop a more systematic method for determining when RUDs are appropriate. Turning first to some general principles for the United States, this Section then proposes two major recommendations: (1) limiting the scope of RUDs and (2) limiting the use of RUDs.

At the outset, the United States should recognize as illustrated by this Note’s case analysis that any limitation to the use of RUDs will not come from U.S. courts, where deference to the U.S. Senate and its RUDs practice remains strong. With the judicial branch largely out of the picture and the President bound to RUDs adopted by the Senate, the Senate holds the keys to the future of RUDs practice. Second, as the Senate ponders its practice, it should note the potential pushback from treaty drafters, who may increasingly limit RUDs, and international courts, which appear willing to enforce these limitations. As previously discussed, given the limited benefits and significant costs associated with RUDs, the United States should avoid overplaying its hand and refrain from overusing them.

The Disabilities Convention provides a helpful illustration. As the Senate Foreign Relations Committee noted in its report, the Disabilities Convention permits reservations, “provided that they are not incompatible with the object and purpose of the Convention.”180 Accordingly, when U.S. senators debated the advice and consent of the Convention in the Senate Foreign Relations Committee, they proposed several RUDs. The reservations were summarized in the report under three areas:

Federalism. The first reservation addresses federalism issues. Article 4(1) of the Convention states that the provisions of the Convention “shall extend to all parts of federal States without any limitations or exceptions.” Because certain provisions of the treaty concern matters traditionally governed by state law rather than federal law, and because in very limited instances some state and local standards are less vigorous than the convention would require, a reservation is required to preserve the existing balance between federal and state jurisdiction over these matters.

Non-Regulation of Private Conduct. The second reservation concerns the extent of the United States obligations under the Convention with regard to private conduct. Although the United States generally and broadly applies nondiscrimination laws to private entities with respect to operation in public spheres of life, some laws set a threshold before their protections are triggered. . . . Accordingly, a reservation is required to make clear that the United States does not accept any obligation under the Convention to enact legislation or take any other measures with respect to private conduct except as mandated by the Constitution and laws of the United States. The committee notes that in a written response for the record, the Department of State and the Department of Justice confirmed that in light of this reservation, ratification of the Disabilities Convention would not impose any new requirements on employers exempted by the Americans with Disabilities Act.

Torture, Cruel, Inhumane or Degrading Treatment. The third reservation concerns the extent of the United States obligations under Article 15 (Freedom from Torture or Cruel, Inhuman or Degrading Treatment or Punishment). As Article 15 of the Convention covers the same subject matter as Articles 2 and 16 of the United Nations Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment and Article 7 of the International Covenant on Civil and Political Rights, the third reservation makes clear that the obligations of the United States under Article 15 of the Convention shall be subject to the same reservations and understandings that apply to U.S. ratification of those two treaties.181

All three reservations stem from the concerns that were raised in Bond about the overreach of a treaty, and the second reservation in essence leaves the Disabilities Convention to have the same effect as the Americans with Disabilities Act,182 a federal statute aimed at protecting persons with disabilities against discrimination. These are not unusual reservations, and consistent with the cases reviewed in Parts II and III, they are likely to be enforced in a domestic or international court.

The RUDs should go no further. Given what this Note uncovers about the jurisprudence of RUDs, whether the drafting of RUDs will preserve their enforcement should not be the limiting factor on a treaty’s ratification. The Disabilities Convention should be considered on its own merits, and the focus should be on whether the RUDs fulfill the United States’ mission to protect persons with disabilities rather than whether domestic courts will enforce them as drafted. Focusing on whether an overly limited RUD will cause improper enforcement of a treaty distracts from the real issue at hand—whether the United States is truly committed to the provisions of the Convention.

But if the Disabilities Convention is an obvious example of a case where U.S. senators should relax their approach to RUDs, UNCLOS provides an illustration of the limits of that reassurance. Perhaps an implicit reaction to the weakness of the “object and purpose” prohibition found and circumvented in many treaties, UNCLOS goes further than the standard VCLT limitation. The Convention provides that “[n]o reservations or exceptions may be made to this Convention unless expressly permitted by other articles of this Convention.”183 Reservations are essentially off the table.

As the preceding Section explained, the real threat to ongoing RUDs practice stems not from the courts but from treaty drafters who might increasingly push for RUD-restrictive provisions. Such reactionary measures may not immediately risk U.S. interests, given the American refusal to sign on to the jurisdiction of international courts and the uncertainty that U.S. courts would ever enforce a treaty provision that restricts RUDs. But as previously discussed, the longer-term effects of overreliance on RUDs remain unknown. The overuse of RUDs might contribute to further restrictions over time, whether through treaty provisions or within international courts, and the U.S. Senate may be forced to ratify fewer treaties unless it changes its RUDs practice. Expanding upon the Disabilities Convention example, this Section proposes two general recommendations for addressing the role of RUDs in the United States’ treatymaking process: (1) limiting the scope of RUDs and (2) limiting the use of RUDs.

1. Limiting the Scope of RUDs

Again, this Note’s case analysis indicates that the possible threat of unintended treaty consequences in domestic courts is minimal: in almost every instance, domestic courts will not challenge RUDs. Given the lack of any domestic threat to their invalidation, the U.S. Senate would be wise to consider how RUDs could be limited to instances in which they are necessary and where they optimize the benefits of treaty ratification.

As discussed in Part II, this Note has recognized a number of latent limitations on RUDs enforceability under domestic law: (1) the condition must have some relationship to the treaty; (2) the Senate cannot use its conditional consent power to alter pre-existing federal law; and (3) the Senate’s conditional consent power should be limited to the extent that it unduly impinges on the prerogatives of the other branches of the federal government. These limitations, while important to note, are focused on ensuring that the United States does not create conflicts for itself. The first and second, for instance, are limitations designed to avoid the situation in Power Authority, where a possible RUD was invalidated because it only addressed matters of domestic concern. The third is included so that the Senate does not override the power of the U.S. House of Representatives or the President in unilaterally passing domestic legislation through the use of RUDs.

Further limitations should look outward at how the United States can avoid conflicts with other states and the international community at large. Toward that goal, RUDs should be avoided except where absolutely necessary to remain consistent with what the United States could legitimately sign onto given its own domestic laws. If the United States decides that it wishes to ratify a treaty, then it should only do so after changing those domestic laws, or otherwise with only the RUDs that are absolutely necessary.184 Encouraging states to find boundaries on their use of RUDs already exists as an enterprise.185 The following principles aim to revive and revise past suggestions, which include recommendations made by scholars proposing looser grounds for RUDs usage.186 In each instance, the proposed principle adheres to the limitation that the RUD does not violate the “object and purpose” of the treaty, an overarching limitation discussed in more detail in the next Section.

First, some have suggested that RUDs are necessary when ratifying treaties that would otherwise create obligations for the United States that would violate provisions of the U.S. Constitution.187 A general RUD that reminds that the Constitution has supremacy over a treaty might demonstrate to treaty partners the limit of the U.S. government’s legal authority given the U.S. Constitution. Such a principle is already well-accepted in constitutional law,188 and albeit unnecessary, the clarification seems relatively benign as long as the RUD is not intended to shield specific treaty provisions that are obviously in conflict with the Constitution. Second, where the United States has to prevent a conflict among U.S. states or existing legislation that already governs and adequately addresses treaty obligations, RUDs can clarify the distinction and boundaries, including whether new legislation would need to be implemented for further legal effects.

But federal and state law in many cases often already “meets or exceeds the requirements” of a particular treaty the United States is considering—the RUDs are therefore intended as an additional protection but are actually not necessary to protect U.S. interests.189 These RUDs should therefore be used to help clarify positions, but not to eschew obligations.Non-self-executing declarations are prime examples of RUDs that avoid obligations; they should therefore be minimized.190 In other words, the United States should not opt for a non-self-executing declaration to avoid its otherwise lack of readiness to abide by certain obligations of a treaty domestically and internationally. Instead, it should determine where the gaps are and attempt to rectify them prior to ratification, and only as necessary, to use specific, narrow RUDs to address the few issues where the United States has a particular concern. Finally, the United States should consider an understanding or a declaration in lieu of reservations, even where a reservation is permitted.191 As the international case law and practice of no-reservation clauses reflect, altering the legal effect of a treaty that has been negotiated and ratified by other states through reservations is a risky practice that should be avoided when a simpler clarification would suffice.192

These recommendations are meant to be consistent with U.S. court jurisprudence that has readily upheld RUDs in many different forms. The main point is to suggest that there is little reason to overuse RUDs when they could be costly from an international perspective and do not have much added value from a domestic perspective. These are not exhaustive recommendations, nor can they apply with equal force in every situation. At the same time, part of the U.S. Senate’s advice and consent process is for the institution to use its best judgment in determining the appropriate role for RUDs. Hopefully, members of the Senate and others involved in the treatymaking process will consider these limitations, and RUDs that are tailored to respond to the international community rather than overestimated domestic concerns will prevail in treaty negotiations.

2. Limiting the Use of RUDs

In cases where appropriately limited RUDs are not possible, such as where a treaty would be inconsistent with the Constitution or other domestic laws and practices, the United States should not ratify the treaty at all. At that point, it should instead first direct its attention to revising these domestic conditions if it genuinely supports a particular treaty. This determination of whether to ratify at all is crucial for avoiding the broad overuse of RUDs. As the case analysis suggests, the determinative factor should be whether the proposed RUDs would violate the “object and purpose” of the treaty. This is the approach already adopted by the VCLT and could be used as a threshold within a state itself for its own deliberations. Note again that the lesson learned from this case analysis is that the choice of whether to ratify should not hinge on the sufficiency or insufficiency of RUDs. Domestic courts will consistently enforce RUDs, and the United States should not refrain from ratifying a treaty because it fears that its RUDs will be found insufficient in domestic courts.

But the United States should refrain from ratifying a treaty if it believes that it is avoiding the treaty’s “object and purpose” by creating RUDs that detract from the treaty’s aims. The aforementioned Senators who raised the concerns over the reservations regarding the Genocide Convention were not only raising a moral argument about the adoption of RUDs. They appealed to the preservation of the international community’s confidence that the United States will meet its treaty obligations and warned about the consequences of encouraging other states to similarly avoid obligations by using RUDs.

Additionally, some scholars argue that a treaty might have one primary “object and purpose,” or might protect a “single, overwhelmingly important right,”193 making RUDs problematic, whereas RUDs attached to treaties involving multiple rights are less likely to sustain such a challenge. Being selective about when to include RUDs depending on the nature of the treaty may therefore also mitigate concerns about their overuse. More broadly, being selective about RUDs in certain treaties may also protect interests for future treaties. Treaties are not ratified in a vacuum, and the defeat of one treaty or the attachment of RUDs may end up affecting the leeway to negotiate another, arguably more important treaty.194 If RUDs are used too prolifically, their effects could become meaningless due to reactionary, no-reservation clauses adopted in future treaties.

As previously acknowledged, the VCLT admittedly provides little guidance about how to define the “object and purpose” requirement, and the United States has not subscribed to it. But again, asking whether a RUD meets the “object and purpose” does not only have to be a VCLT-oriented or international law inquiry; it can be an internal, domestic dialogue that should already be happening in Senate hearings over treaties, but often is not, as other questions about the unintended domestic consequences take precedence. The inquiry is a means to directly engage with the concerns discussed in Section IV.A.

Lastly, it is worth noting that there is no guarantee that the domestic case law will continue its favorable treatment of RUDs if more treaties expressly limit RUDs and international courts increasingly invalidate RUDs. If international courts begin invalidating more RUDs, whether under the “object and purpose” requirement or other treaty provisions, it will likely place more pressure on U.S. courts to at the very least consider these objections from other states and parties. Of course, it is quite possible given the robust domestic jurisprudence in U.S. courts that even these treaties’ RUDs will be honored, but rather than bank on this possibility, the United States would be wise to focus on trying to develop a sustainable RUDs practice.


The question of whether RUDs are and will remain valid and enforceable remains central to the future of treatymaking. If courts of law will enforce them, RUDs could remain a primary, if not necessary, tool for treaty participation. If they will not, states (including the United States) are left to more drastic alternatives, including not ratifying treaties at all. These concerns over the sufficiency and, in turn, the sustainability of RUDs are important dimensions of scholarly and policy debates. While some scholars have long defended the practice of RUDs as valid exercises of the U.S. Senate’s powers, the use of RUDs has also long been a target of criticism. This Note adds a new dimension to that debate: U.S. and international court enforcement of RUDs appears to be robust, except for international courts invalidating RUDs that conflict with express treaty limitations. Consequently, the Senate’s current prioritization of the domestic unintended consequences is misguided and risks undesirable consequences, including encouraging more treaties that limit RUDs and constraining the United States from participating in treatymaking in the future.

Rather, if RUDs are enforceable, recent jurisprudence points more to the costs of overusing RUDs than to their benefits. The United States and other states should therefore avoid drafting elaborate RUDs that are more likely to attract negative attention within international courts and the international community. As this Note has attempted to illustrate, the biggest threat to RUDs is not their insufficient drafting, but rather their overuse. The limited benefits to drafting stronger RUDs hardly outweigh the significant costs associated with adopting those RUDs.

The future of RUDs is in the hands of the United States and its fellow states. Without any significant risks to the domestic invalidation of RUDs, there is no need for the United States to overuse RUDs and risk broader treaty formulation and compliance among states. RUDs that go further than the necessary bounds in which they have so far been sustained might lead to their own demise. Instead, the United States has the ability to help lead a reoriented effort to sustain limited RUDs, and in turn, to sustain the values of treatymaking.

For the Appendix to this Note, please see the PDF version.