This paper studies the causal effect of immigration on crime in the context of the massive influx of Syrians to Türkiye, using comprehensive data that spans all stages of the judicial process—from prosecution to incarceration—and includes information on the nativity status of both perpetrators and victims. To isolate causal effects, we employ a two-stage least squares (2SLS) estimation technique, exploiting substantial exogenous variation in the migrant-to-native ratio that arises from the geographical proximity of Turkish provinces to Syrian governorates. The findings reveal a slight increase in total crime at the prosecution stage, while no significant effects are detected for criminal court cases or convictions. Moreover, natives experience increased victimization at the prosecution stage, while their involvement in criminal activities remains unchanged. In contrast, both the likelihood of committing a crime and being a victim of crime increase among immigrants. The analysis further suggests that immigrants may be crowding out natives in specific crime categories, such as smuggling.