This article tests the impact of Walmart's corporate decisions to end the sale of handguns at its stores in 1994 and to discontinue the sale of all firearms at approximately 59% of its stores in 2006 before resuming firearms sales at some of those stores in 2011. Using a difference-in-differences framework, we find that that from 1994 to 2005 counties with Walmarts robustly experienced a reduction in the suicide rate and experienced no change in the homicide rate. These models suggest that Walmart's policy change caused a 3.3 to 7.5% reduction in the suicide rate within affected counties, which represents an estimated 5,104 to 11,970 lives saved over the studied period (425-998 per year). In contrast, Walmart's 2006 and 2011 decisions to discontinue and subsequently resume the sale of rifles and shotguns in many of its stores was not associated with a robustly measured effect on homicide or suicide rates. We do find evidence that Walmart's 2006 decision to reduce the number of its stores that sold firearms caused a statistically significant reduction in the suicide rate for counties in which Walmart did not subsequently resume firearms sales.
Ayres, I., Shelley, Z., & Vars, F. E. (2020). The Walmart Effect: Testing Private Interventions to Reduce Gun Suicide. Journal of Law, Medicine and Ethics, 48(4_suppl), 74–82. https://doi.org/10.1177/1073110520979404