According to a study by the Department of Justice, between 19, federal, state, and local agencies conducted background checks on more than 180 million firearm applications and denied 2.82 million gun sales to prohibited purchasers. Though majority of the transactions and denials reported by FBI and BJS are associated with a firearm sale or transfer, a small number may be for concealed carry permits and other reasons not related to a sale or transfer.
To date, the background check system has blocked over 3 million firearm sales to prohibited purchasers. "Background Checks for Firearm Transfers, 2013-2014." Bureau of Justice Statistics. A case-control study of 11 cities found that in a domestic violence situation, the perpetrator’s access to a gun increased the odds of femicide by more than five times (adjust OR=5.44, 95% CI = 2.89, 10.22). Campbell, Daniel Webster, and Jane Koziol-Mc Lain, "Risk Factors for Femicide in Abusive Relationships: Results from a Multisite Case Control Study," American Journal of Public Health 93, no. Both the Centers for Disease Control and Prevention (CDC) and the FBI collect data on firearm homicides — the former from medical examiners and the latter from local law enforcement. The CDC’s National Vital Statistics System records a higher percentage of all firearm deaths but fails to capture details about their circumstances, including the relationship of the perpetrator to the victim.
This makes it unsuitable for measuring gun violence between people of certain relationships.
In contrast, the FBI’s Supplementary Homicide Reports (SHR) include details on the perpetrator and weapon but are more likely to be missing records because the FBI relies on police departments to voluntarily submit their homicide data on an annual basis.
Over the last five years of available data, 55% of women killed by intimate partners (including same-sex partners) were killed with guns.
Non-random samples occur when there is no chance of including all members of a population.
Erin Grinshteyn and David Hemenway, "Violent Death Rates: The US Compared with Other High-income OECD Countries, 2010," American Journal of Medicine, 2015.
The World Bank defines a high-income country as one with a gross national income per capita greater than ,736.
Of the 175,703 firearm deaths in the US from 2012 to 2016 (the most recent five years of data available), 108,183 (or 62 percent) were suicides.
To calculate this total, Everytown relies on CDC data regarding fatal injury by intent.