Using data from the Federal Bureau of Investigation’s Uniform Crime Report program and differences in the timing of the reform’s introduction, we find that unilateral divorce caused an increase in violent crime rates of approximately 9% during the period 1965–96. When we use age at the time of the reform as an additional source of variation, our findings suggest that young adult cohorts, who were children at the time of the reform, were particularly affected. Finally, we show evidence that a potential channel behind our findings is an increase in poverty and inequality among mothers who were “surprised” by the reform.