High-school exit exams have fallen out of favor in recent years, after research showed that pinning graduation to passing a high-stakes test can push some students to drop out. The future can be grim without a diploma: dropouts have higher rates of unemployment, earn far less money on the job, have poorer physical and mental health, and are more likely to be incarcerated. Wary of such risks, 18 states have dropped exit exams from their diploma requirements in the past two decades. This year, graduation requirements in just 11 states include an exit exam. Beyond high-school dropout and graduation rates, exit exams might have other effects on students and communities. Little is known, for example, about the specific effects of exit exams on crime. Conventional belief holds that more and better-quality education reduces crime. Could exit exams improve teaching and learning in high schools such that criminal activity drops? The author looked at the arrest rates of jurisdictions and compared them during periods before and after graduation requirements were made more demanding in two ways: adding high-school exit exams and increasing the amount of academic coursework. The author finds that requiring exit exams decreases arrests by approximately 7 percent, primarily from a decrease in property crimes. Increasing course requirements, however, has no significant effects. The analysis supports earlier research regarding the beneficial effects of exit-exam use and is also one of the few studies to show that specific education policies can have crime-reducing effects. As decision-makers consider reinstating tests, these findings may be of particular relevance. While exit exams have come under fire for pushing students at the margins out of high school, the author's analysis indicates that they have more broadly positive effects on communities than previously understood.