Recent mass shootings in Tulsa, Oklahoma; Uvalde, Texas; and Buffalo, New York are just three of the 233 mass shootings in the U.S. this year — down slightly from 240 mass shootings at this time last year, according to tallies from the Gun Violence Archive, an independent, nonprofit project unaffiliated with an advocacy group.
The Gun Violence Archive defines a mass shooting as a shooting in which “4 or more shot or killed, not including the shooter.”
Those are also the three recent mass shootings in the U.S. that have received widespread national media coverage and have renewed calls for expanded gun regulations, including background checks, even from some who generally support gun ownership.
For example, several performers dropped out of the National Rifle Association’s annual convention held May 27 in Houston, three days after the Uvalde shooting. Country and gospel singer Larry Gatlin withdrew, saying he agrees with “most of the positions held by the NRA,” but has “come to believe that, while background checks would not stop every madman with a gun, it is at the very least a step in the right direction toward trying to prevent the kind of tragedy we saw this week in Uvalde — in my beloved, weeping Texas.”
Here, we update our summary of academic research on background checks, originally published in 2019, with the latest analyses. In general, academic studies do not show that background checks alone for firearm purchases substantially reduce firearm deaths.
Instead, research suggests universal background checks can be effective when combined with licensing strategies, such as permit-to-purchase. With permit-to-purchase, a gun buyer must pass a background check to obtain a permit to then purchase a firearm.
Regulated and unregulated gun markets
The phrase “universal background checks” typically refers to a broad regulatory framework in which all legal gun buyers would be subject to a criminal and mental health background check before completing a gun purchase.
Right now, for certain gun sales in certain states, sellers do not have to run a background check on customers. This is sometimes called the “gun-show loophole.”
People buying from federally licensed dealers at gun shows do need to pass a background check.
But direct private sales between people living in the same state, such as private sales at gun shows or online, do not require a background check — though 14 states plus the District of Columbia require universal background checks for all types of gun sales. Three states — Hawaii, Illinois and Massachusetts — require buyers to have gun permits, which are only issued after a background check is completed.
A brief history of federal regulation of gun sales
The Gun Control Act of 1968 was the first federal legislation that aimed to track firearm commerce. It established the federal licensing system for firearms dealers. The act applies to people who sell guns as a business.
The Firearm Owners Protection Act of 1986 limited the federal government’s authority in enforcing the Gun Control Act. For example, the Firearm Owners Protection Act limits how often federal agents can inspect gun dealers for violations. The Firearm Owners Protection Act also makes clear that private sales are precluded from regulation:
A person who engages in “occasional sales, exchanges, or purchases of firearms for the enhancement of a personal collection or for a hobby, or who sells all or part of his personal collection of firearms” doesn’t need a federal license, according to the 1986 act.
The national instant criminal background check system, or NICS, was established in 1998 as part of the Brady Handgun Violence Prevention Act — sometimes called the Brady Act, Brady Bill or Brady Law — which President Bill Clinton signed in 1993.
The law was named for and championed by James Brady, onetime press secretary to President Ronald Reagan. Brady was shot in the head in March 1981 during an assassination attempt on Reagan. Brady lived with physical disabilities for the rest of his life. His death in 2014 was ruled a homicide.
The Brady Law imposed a five-day waiting period before a licensed dealer could transfer a handgun to a buyer. This provision expired, as intended, in 1998. A permanent provision that went into force that year established the federal background check system that now exists. The Bureau of Alcohol, Tobacco, Firearms and Explosives is responsible for enforcing federal gun control legislation. The FBI runs background checks.
There are 37 jurisdictions in which sellers contact the FBI directly for checks. In 13 states, state agencies conduct checks by electronically accessing the NICS. The rest of the states have a mix of checks that either the state or FBI conducts, depending on the type of gun being purchased.
Federally licensed and private vendors both sell at gun shows. An analysis of how gun owners got their firearms, published in 2017 in the Annals of Internal Medicine, included 1,613 adult gun owners who took a nationally representative, web-based survey. This survey found 22% of participants obtained firearms within the last two years without a background check. News outlets and academic researchers regularly cite this survey as the best available estimate. The analysis was primarily funded by organizations that support stricter gun control, but the authors note in their paper that the “funders did not play a role in the design, conduct, or reporting of the research or in the decision to submit the manuscript for publication.”
Gun buyers are more likely to undergo a background check in states that have background check laws, compared with states that do not, according to February 2022 research in the American Journal of Preventive Medicine.
Another survey, conducted in 2018 among 2,558 adults in California and published in Preventive Medicine, found 17% of “firearm owners who purchased their most recent firearm within California in 1991 or later, following implementation of the state’s comprehensive background check law, reported doing so without a background check.”
Do Americans want background checks?
Yes, research suggests most Americans want some form of government regulation determining whether someone buying a gun is eligible to do so.
A Pew Research poll of 5,109 U.S. adults conducted in April 2021 finds 87% of gun owners and 88% of non-gun owners think “people with mental illnesses” should not be able to buy guns, while 72% of gun owners and 87% of non-gun owners think gun show sales and private gun sales should be subject to background checks.
The same poll finds 70% of Republicans and 92% of Democrats favor “subjecting private gun sales and gun show sales to background checks.” Support for other proposals, like assault weapons bans or a federal database to track gun sales, tend to fall along partisan lines, with Democrats more widely supportive than Republicans, according to Pew.
Similarly, the authors of an August 2021 paper in Preventive Medicine studied two rounds of the John Hopkins’ National Survey of Gun Policy — from January 2017 and January 2019 — with 3,804 U.S. adults responding. They find broad support for background checks and licensing across races and ethnicities. Some 76% of white, 77% of Black and 78% of Hispanic respondents favor requiring gun buyers to get a license from local law enforcement prior to purchase. And 89% of white, 82% of Black and 88% of Hispanic respondents favor background checks for all gun sales, the paper finds.
The ATF keeps an updated list of state gun laws. Identifying information on federal background check records are destroyed within 24 hours after the check is completed if the check shows the individual is allowed to own a gun. This period was previously 90 days, but the Department of Justice shortened the period to no more than 24 hours in the mid-2000s. Five states — Connecticut, Hawaii, Massachusetts, New Jersey and New York — do not prohibit municipalities from enacting their own gun laws.
The FBI has completed roughly 425 million firearm background checks since 1998. It conducted about 39 million checks in 2020 and 2021 each, up substantially from 28 million in 2019 and 26 million in 2018.
There are 12 reasons the FBI denies gun sales. From November 1998 through May 2022, the FBI denied nearly 2.1 million gun sales. About half of those denials were because the potential purchaser had been convicted of a crime punishable by more than one year in prison, or a misdemeanor punishable by more than two years.
If the FBI cannot complete a background check within three days, a federally licensed dealer may — but isn’t required to — complete the sale. From 2006 to 2015, there were roughly 6,700 guns sold to people with domestic violence records after the FBI did not meet the three-day deadline, according to an analysis from the Government Accountability Office. Several states allow the three-day federal deadline to be extended.
The number of firearms sold after the three-day deadline to people who should have been denied has doubled in recent years, according to a Wall Street Journal analysis. The U.S. Senate hasn’t taken up a bill the House passed in March 2021 that would extend the deadline to at least 10 days.
Gun buyers denied on the regulated gun market may turn to the unregulated market. Some three-quarters of people incarcerated for gun crimes got their firearms from someone who did not legally have to conduct a background check, according to a 2017 review of research and state gun laws published in the Journal of Law, Medicine and Ethics.
An analysis of a nationally representative survey of 1,444 gun owners, conducted in 2016 and published in Preventive Medicine in June 2021, parsed 238 respondents who had also sold a firearm in a private sale. Less than half — 46% — of those private gun sellers thought they bore responsibility for checking if their buyers were eligible to buy guns.
To recap, some legal gun sales are regulated, others are not. Around one-fifth of legal gun sales are unregulated, according to the latest research. Gun buyers are more likely to undergo a background check in states that have background check laws.
A gun store owner has to be federally licensed, run background checks on customers and record firearm sales. Someone conducting a private gun sale online doesn’t need to run a background check or record the sale. Licensed and unlicensed vendors sell side by side at gun shows. Another bill the U.S. House passed in March 2021 would require background checks for private sales. The Senate has not taken up that bill either.
Formative research findings
One of the first studies to look into the Brady Law was published in August 2000 in the Journal of the American Medical Association. The authors analyzed firearm homicides and suicide rates from 1985 to 1997 in the 32 states that did not already have comparable legislation. As a control, they also analyzed those rates in the 18 states with similar legislation. Homicide and suicide rates didn’t change much after the law was enacted, the authors found. Only the rate of firearm suicides for people aged 55 and older declined. This relationship was particularly evident in states with waiting periods and background checks, as opposed to only background checks. In a blog post, the authors characterize the Brady Law as having a “useful — but modest” effect on keeping guns out of the hands of people who the federal government prohibits from having them. They note that the secondary gun market is unregulated, as it remains today.
A task force of doctors from government agencies and academia in 2005 published a comprehensive literature review in the American Journal of Preventive Medicine on whether firearm laws reduce violence. The authors found four studies, including the one mentioned above from JAMA, that explored background checks. They note that the suicide reduction observed among people age 55 and older seems linked to waiting periods and not necessarily to felony restrictions. Another early study, published in 1999 in the American Journal of Public Health and mentioned in the literature review, found that denying handgun sales to felons was associated with a 20% to 30% lower risk of those felons committing new gun-related or violent crimes.
The JAMA and AJPH studies aren’t necessarily contradictory. They simply take different approaches. The JAMA study looked at violence that happened before and after the Brady Law. The AJPH study tried to peer at the other side of the coin — at violence prevented.
Recent research suggests coupling background checks with permitting programs is an effective way to curb gun violence
There is not much recent, federally-funded research on gun violence. In 1996, Congress prohibited the Centers for Disease Control and Prevention from using federal funds to “advocate or promote gun control.” That means there has historically been little federal funding to examine gun violence on a national scale.
But in December 2019, Congress allocated $12.5 million apiece to the Centers for Disease Control and Prevention and the National Institutes of Health to study gun violence in fiscal year 2020. Congress made the same allocation for 2021. Results from some of those initially funded studies, including a $2 million study exploring which safety strategies effectively deter school shootings, could be published later this year.
One academic analysis, not funded by the recent federal allocations, found no impact on violent crime in the two years after Massachusetts passed legislation in 2014. The law, among other things, expanded the reasons a prospective gun buyer could be denied a state firearm license, according to the paper published in March 2021 in Justice Quarterly. The author notes that “unlike California’s gun control laws, [the] Massachusetts Department of Mental Health is not required to transmit records of individuals ordered to undergo involuntary outpatient treatment, which may limit the effectiveness of background checks conducted on potential buyers.”
In February 2019, researchers writing in the Annals of Epidemiology examined California’s longstanding background check law. The authors looked at elements of the law that require criminal background checks for almost all gun sales in the state and prevent nearly everyone convicted of violent misdemeanors from buying a firearm for a decade. There was no association between those rules and changes in the firearm homicide rate in California, according to the paper. The authors note incomplete data and potential lack of enforcement could affect their findings.
Another study from July 2018, published in Epidemiology, likewise found no apparent association between repeals of comprehensive background check laws in Indiana and Tennessee and changes in firearm suicide and homicide rates in those states.
A study from 2016 published in The Lancet analyzed firearm-related deaths in all states from 2008 to 2010. This study considered how different gun control laws — 25 in all — affect firearm death rates. The study was cross-sectional, meaning it offered a snapshot in time. The authors found that federally-mandated, universal background checks could reduce firearm deaths in the U.S. by 57%. But behavioral scientists at RAND Corp., a nonprofit, nonpartisan research and analysis organization, took exception to the paper, citing “a number of serious analytical errors that we suspected could undermine the article’s conclusions.”
RAND authors Terry Schell and Andrew Morral write: “Our corrected analyses found no statistically significant evidence for any of the article’s major conclusions.” The lead author of The Lancet paper, Bindu Kalesan, and her co-authors responded, describing Schell and Morral’s analysis as “a skewed reading of the evidence, and a singular view of common sense.”
The research is clearer that background checks can reduce gun violence when those checks are done in tandem with permit-to-purchase programs. A September 2020 paper in the American Journal of Public Health examining gun laws in four states — Connecticut, Maryland, Missouri and Pennsylvania — found no clear association between background checks alone and firearm deaths, but “licensing laws coupled with [background checks] requirements were consistently associated with lower firearm homicide and suicide rates,” the authors write.
A June 2018 study in the Journal of Urban Health found that for large, urban counties, permit-to-purchase laws were associated with a 14% drop in firearm homicides. Comprehensive background checks alone, meanwhile, were associated with increases in firearm homicide in large urban areas. The permitting process, “may include a more thorough background check which law enforcement can take 30 days or more to complete,” the authors write.
Connecticut implemented a permit-to-purchase law in 1995. Over the next decade, the law was associated with a 40% drop in firearm homicide rates, according to August 2015 research in the American Journal of Public Health. In Missouri, firearm homicide rates increased 23% in the three years after Missouri repealed its permit-to-purchase requirement in 2007, according to an April 2014 study in the Journal of Urban Health.
“Given the body of evidence on the effectiveness of licensing laws and the increasing levels of support among the population, including gun owners, policy makers should consider handgun purchaser licensing as a complement to [comprehensive background check] laws,” conclude Johns Hopkins University researchers Cassandra Crifasi, Alexander McCourt and Daniel Webster in their June 2019 white paper on permit-to-purchase programs.
A January 2020 study in Pediatrics is one notable exception to the findings on background checks plus permit-to-purchase programs being more effective than background checks alone. The authors examined responses from nearly 180,000 high school students covering 1993 to 2017 from the Youth Risk Behavior Survey, which the Centers for Disease Control and Prevention conducts every other year.
An average of nearly 6% of the youth surveyed across the years reported carrying a gun during the past month. But just 17% of them were from states with universal background checks — 83% were from states without those checks. While the authors studied youth gun carrying, not gun violence, they note that access to guns generally increases risk of injury or death.
Absent national policy some states have sought to regulate gun purchases, but those laws may be less effective when neighboring states have looser policies. A May 2022 study in Preventive Medicine examined the prevalence of gun shows in 2018 across 3,107 counties in the contiguous U.S. Gun shows, the authors find, cluster in counties next to states that have universal background checks. “Our results provide evidence that proximity to states without universal background check laws inherently supports gun trafficking,” the authors write.
Likewise, a July 2021 paper in the Journal of Injury and Violence Research finds the reduction in firearm homicides in counties in states with background check or permit laws is muted when those counties lie near states without those regulations.
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