Luca, MichaelMalhotra, DeepakPoliquin, Christopher William2017-11-212017Luca, Michael, Deepak Malhotra, and Christopher Poliquin. 2017. “Handgun Waiting Periods Reduce Gun Deaths.” Proceedings of the National Academy of Sciences 114 (46) (October 16): 12162–12165. doi:10.1073/pnas.1619896114.0027-8424http://nrs.harvard.edu/urn-3:HUL.InstRepos:34372583Handgun waiting periods are laws that impose a delay between the initiation of a purchase and final acquisition of a firearm. We show that waiting periods, which create a “cooling off” period among buyers, significantly reduce the incidence of gun violence. We estimate the impact of waiting periods on gun deaths, exploiting all changes to state-level policies in the Unites States since 1970. We find that waiting periods reduce gun homicides by roughly 17%. We provide further support for the causal impact of waiting periods on homicides by exploiting a natural experiment resulting from a federal law in 1994 that imposed a temporary waiting period on a subset of states.en-USgun policygun violencewaiting periodinjury preventionJournal Article2017-11-2110.1073/pnas.1619896114