Secure Communities is a recently introduced immigration enforcement policy in the United States, intended to improve public safety by making it easier to identify and deport criminal immigrants and immigration violators. In this article, we examine the effect of Secure Communities on crime by utilizing the variation in its timing of activation across counties. We extend previous research by exploring potential crime spillovers associated with Secure Communities, in which its activation in one jurisdiction affects crime rates in a neighboring jurisdiction. Estimation results suggest that the activation of Secure Communities influenced crime rates in both the activated area and neighboring areas in important ways. We find that Secure Communities led to a significant crime reduction in the activated area if it is also activated in neighboring areas, but no significant local crime reduction is observed if not activated in neighboring areas. Likewise, its activation is often associated with significant crime spillovers into neighboring areas, but this displacement effect is often completely eliminated if Secure Communities is activated in the neighboring areas as well.

中文翻译：

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安全的社区会带来更安全的社区吗？移民执法、犯罪威慑和地理外部性

安全社区是美国最近推出的一项移民执法政策，旨在通过更容易识别和驱逐犯罪移民和移民违规者来改善公共安全。在本文中，我们通过利用其在各县激活时间的变化来检验安全社区对犯罪的影响。我们通过探索与安全社区相关的潜在犯罪溢出效应来扩展先前的研究，其中安全社区在一个司法管辖区的激活会影响邻近司法管辖区的犯罪率。估计结果表明，安全社区的激活在重要方面影响了激活区域和邻近区域的犯罪率。我们发现，如果在邻近地区也激活安全社区，则安全社区会显着减少激活地区的犯罪，但如果不在邻近地区激活，则不会观察到显着的地方犯罪减少。同样，它的激活通常与向邻近地区的重大犯罪溢出有关，但如果在邻近地区也激活安全社区，这种置换效应通常会完全消除。