The Yale Law Journal

October 2012

How Much Difference Does the Lawyer Make? The Effect of Defense Counsel on Murder Case Outcomes

James M. Anderson & Paul Heaton
122 Yale L.J. 154 (2012).

One in five indigent murder defendants in Philadelphia is randomly assigned representation by public defenders while the remainder receive court-appointed private attorneys. We exploit this random assignment to measure how defense counsel affect murder case outcomes. Compared to appointed counsel, public defenders in Philadelphia reduce their clients’ murder conviction rate by 19% and lower the probability that their clients receive a life sentence by 62%. Public defenders reduce overall expected time served in prison by 24%. We find no difference in the overall number of charges of which defendants are found guilty. When we apply methods used in past studies of the effect of counsel that did not use random assignment, we obtain far more modest estimated impacts, which suggests defendant sorting is an important confounder affecting past research. To understand possible explanations for the disparity in outcomes, we interviewed judges, public defenders, and attorneys who took appointments. Interviewees identified a variety of institutional factors in Philadelphia that decreased the likelihood that appointed counsel would prepare cases as well as the public defenders. The vast difference in outcomes for defendants assigned different counsel types raises important questions about the adequacy and fairness of the criminal justice system.