One of the central debates animating the interpretation of gun research for public policy is the question of whether the presence of firearms independently makes violent situations more lethal, known as an instrumentality effect, or whether determined offenders will simply substitute other weapons to affect fatalities in the absence of guns. The latter position assumes sufficient intentionality among homicide assailants to kill their victims, irrespective of the tools available to do so. Studies on the lethality of guns, the likelihood of injury by weapon type, offender intent, and firearm availability provide considerable evidence that guns contribute to fatalities that would otherwise have been nonfatal assaults. The increasing lethality of guns, based on size and technology, and identifiable gaps in existing gun control policies mean that new and innovative policy interventions are required to reduce firearm fatalities and to alleviate the substantial economic and social costs associated with gun violence.

https://doi.org/10.1146/annurev-criminol-061020-021528