Viola Salvestrini (Bank of Italy)
Maddalena Ronchi
We study how gender composition affects team decision-making using a novel dataset on collegial rulings from Italian criminal courts. Exploiting quasi-random assignment of judges and cases to three-judge panels, we find that all-women teams convict more often and issue the most appeal-proof rulings. All-men teams convict less frequently and have the lowest appeal-proof rate, while mixed-gender teams resemble all-men teams in conviction rates but nearly match all-women teams in accuracy. This rules out leniency as the main explanation and points instead to differences in diagnostic skills and coordination frictions. Analyses of written opinions, deliberation times, and entry exam scores suggest these differences are effort-driven rather than reflecting innate ability. We formalize these patterns in a structural model where judges' leniency and diligence drive diagnostic skills through endogenous effort. Estimation reveals diligence as the dominant driver of the cross-team quality gap and quantifies the role of frictions in mixed-gender teams. Counterfactual exercises show that equalizing men's diligence to women's would largely close the quality gap, and that the ongoing feminization of the judiciary implies a trade-off between aggregate decision accuracy and trial duration.