A partner in crime: Assortative matching and bias in the crime market

In the market for criminals the Prisoner's Dilemma creates an incentive for every criminal to find a partner with a higher likelihood of success in evading arrest. If no one is arrested, no one will have to talk to the police about the partnership and be at fault for the arrest of the other partner. This incentive leads to an equilibrium pattern of Positive Assortative Matching (PAM) on the likelihood of success. Using individual matched report-arrest data from the National Incident Based Reporting System and a novel empirical strategy, I find that offenders generally match according to PAM on the probability of success. I find that matching between criminals of different race can be subject to search frictions such as availability of potential partners. Matching between genders is likely biased, as females have a higher probability of success than males, contrary to unconditional success ranking. This bias persists in groups of three but diminishes in matches between older criminals, consistent with notions of discrimination. The results are of interest to policy makers who want to impede criminals from organizing.