Rewards, sanctions, and trust in the police: evidence from field and survey experiments in Colombia

What the police do, and how civilians interpret their actions, shapes institutional trust and the legitimacy of law enforcement. Yet in many democracies, both officer behaviuor and public expectations remain fragile. This paper studies how expectations about police enforcement align–or misalign–with actual patterns of behaviuor among future Colombian officers. Using a behavioural game and an incentivized prediction survey, we analyze how police trainees choose between sanctions and rewards under discretionary conditions and how civilians anticipate these choices. Our findings show that while resource distributions were generally equitable, police students were more likely to reward in-group members and sanction out-group members. Citizens, however, systematically overestimated the officers' willingness to enforce fairness, particularly through sanctions. Moreover, incentivizing prediction accuracy improved belief calibration. By combining experimental games and incentivized belief surveys, our study contributes to the literatures on discretionary policing and public trust by illustrating how identity and incentives shape both police behaviuor and citizen expectations.