Does the certainty of arrest reduce domestic violence? Evidence from mandatory and recommended arrest laws

Domestic violence remains a major public policy concern despite two decades of policy intervention. To eliminate police inaction in response to domestic violence, many states have passed mandatory arrest laws, which require the police to arrest abusers when a domestic violence incident is reported. Using the FBI Supplementary Homicide Reports, I find that mandatory arrest laws actually increased intimate partner homicides. I discuss two potential mechanisms for this increase in homicides: decreased reporting by victims and increased reprisal by abusers. I investigate validity of these hypotheses by examining the effect of mandatory arrest laws on different sub-groups and by analyzing family homicides where the victim is less often responsible for reporting. There appears to be consistent evidence for the reporting mechanisms. For family homicides, mandatory arrest laws appear to reduce the number of homicides. This study therefore provides evidence that these laws may have perverse effects on intimate partner violence, harming the very people they seek to help.