Abstract:
There are several strategies available to police “stopping” suspects. Most efficient is to stop only
members of the group with the highest a priori probability of guilt; least efficient is indiscriminate
stopping. An efficient option that satisfies one criterion for fairness is a strategy that matches stop
probability to risk probability. But a strategy that chooses stop probabilities so that the absolute
number of innocents stopped is equal for all groups is close to maximally efficient and seems fair
by almost any criterion.