In 1996, Congress expanded the federal Gun Control Act (GCA) to prohibit defendants convicted of a qualifying domestic violence misdemeanor from possessing or purchasing a firearm. Using the FBI’s Supplementary Homicide Reports along with homicide data collected from selected state law enforcement agencies, I investigate if this expansion was successful in reducing homicides among the target groups. I use variation from a legal loophole and a series of circuit court decisions to generate difference‐in‐differences estimates. I find evidence that the GCA expansion led to 17 percent fewer gun‐related homicides among female intimate partner victims and 31 percent fewer gun homicides among male domestic child victims. The law also has protective benefits for those that were not targeted by the legislation. “Other” family members (parents and siblings) also experience a 24 percent reduction in gun homicides. I find no evidence that reductions in gun homicides were offset by an increase in nongun homicides. While most falsification and robustness tests support the above conclusions, some tests suggest caution when interpreting the results and a need for further research.