We analyze the consequences of using driver consent as a basis for initializing a traffic stop-and-search compared to those searches based on probable cause. We find that consent searches are less likely to result in contraband recovery than are probable cause searches. Moreover, police agencies with a relatively higher reliance on consent searches find similar amounts of contraband and make a similar number of arrests as agencies doing much less searching but with a greater reliance on probable cause. These patterns are amplified along racial lines, and there is no discernible relationship between the use of consent searches and crime. We also provide causal evidence that corroborate these observational findings by examining the consequences of a Texas Highway Patrol policy, which suddenly increased the consent search rate in two South Texas counties. We show the contraband recovery rate discontinuously decreases when the consent search rate discontinuously increases.

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同意搜索：评估常见且高度自由裁量权的警察做法的有用性

与基于可能原因的搜索相比，我们分析了使用驾驶员同意作为初始化交通停车搜索的基础的后果。我们发现，与可能原因搜查相比，同意搜查不太可能导致违禁品被追回。此外，相对较高程度依赖同意搜查的警察机构发现的违禁品数量和逮捕人数与搜查次数少得多但更依赖可能原因的机构相似。这些模式沿着种族界限被放大，并且使用同意搜查和犯罪之间没有明显的关系。我们还提供了因果证据，通过检查德克萨斯州高速公路巡逻政策的后果来证实这些观察结果，该政策突然增加了德克萨斯州南部两个县的同意搜索率。我们发现，当同意搜索率不连续增加时，违禁品回收率不连续下降。