Arrest as a preferred response to incidents of intimate partner violence has had some unintended consequences, not the least of which is an increase in dual arrests. Arresting both parties may mean that the victim is getting arrested along with the assailant, which is clearly problematic. To discourage dual arrests, many states have enacted legislation to mandate that responding officers determine the primary or predominant aggressor. But have these laws been effective? Until now no comprehensive research has examined this issue.The presenters will discuss a 10-year study of the impact of intimate partner violence primary aggressor laws on single and dual arrest. The study took into account such factors as seriousness of offense and the disparate impact on White and non-White and heterosexual and same-sex couples. Presenters will discuss their results as well as policy implications.