Demographic disparities in bar exam pass rates are problematic but poorly understood. We investigate a possible explanation: participation in extracurricular activities, which could either distract from bar exam preparation or motivate and prepare students to succeed. Generally, participation in extracurricular activities while in law school does not play a large role in bar exam success. However, there is a significant, arguably causal, penalty associated with one particular activity–pro bono work–most notably in lower-ranked law schools. This penalty is sizable: pro bono work is associated with a 5 percentage point (6%) decrease in the chances of passing the bar exam on the first attempt. This penalty is largest for Black and female students and may explain as much as 20% of the Black-white gap in first-attempt bar pass rates.