A popular proxy for gun ownership is the fraction of suicides from firearms. This has made identifying the causal effect of guns on suicide difficult. In this article, firearm background checks are used as a proxy for changes in gun ownership rates, allowing the effect of guns on suicide to be identified. The results from panel data regressions show that increases in firearm background checks rates are associated with increases in firearm suicide rates. Overall suicide is positively, but insignificantly, related to background checks. To alleviate endogeneity that comes from suicidal individuals purchasing a gun to commit suicide, youth suicide is analysed and yields similar, but noisier results.