The finding indicated that all types of firearms were found to significantly increase the chances of an incident resulting in a lethal outcome. Shotguns were shown to be the most lethal because they tend to be more powerful weapons. Handguns closely followed since they are more concealable and useful for close-range confrontations. The least lethal firearms were found to be rifles, since they are not easily concealed and it takes a trained or skillful marksman to hit a moving target. Firearms increase lethality dramatically, not only are injuries incurred by them traumatic to the body, but they also require less sustained physical and psychological effort to use them compared to other types of weapons. Incident circumstance variables, including incidents occurring during the course of criminal or crime-related activity, and lovers’ quarrels were compared and found to be significantly related to increased chances of lethality. Those engaging in felonious activity, drug deals, and gang disputes were likely to be more willing to use force to achieve their goals or to assert themselves violently should a confrontation arise. In the case of lovers’ quarrels, there is a higher level of emotion involved, which may exacerbate a violent situation, making it more likely to turn deadly. Regarding location, only the open access category was significantly related to lethality, and this resulted in an increased chance of death compared to incidents occurring within a residence. Males were both more likely to die and more likely to kill within a violent confrontation. The most striking finding was that automatic firearm variants were not significantly more lethal than their semiautomatic counterparts. The research analyzed data from the National Institute Based Incident Reporting System (NIBRS) collected by the Federal Bureau of Investigations (FBI) from 1995 to 2000. Limitations, program development, and legislation are discussed. Tables, references