How Firearm Background Checks Work

Brian O'Connor (L) of Newtown, Conn. fills out paperwork to purchase a Glock 10mm pistol at Chris' Indoor Shooting Range in Guilford, Conn. See more firearms pictures.
REUTERS/ Michelle McLoughlin

Like clockwork, after each mass shooting that shocks the U.S., the topic of "gun control" dominates media and politics. It was everywhere after Colorado's Columbine High School rampage of 1999, 13 dead; the Virginia Tech massacre of 2007, 32 dead; the 2011 shootings outside a grocery store in Tucson, Ariz., six dead and congresswoman Gabby Giffords critically injured; the 2012 shootings in a Colorado movie theater, 12 dead; and later that year the slaughter of 20 first graders and six adults at Sandy Hook Elementary in Connecticut.

After expressing shock and grief over the killings, the conversation often turns to firearm background checks. Mandatory background checks are intended to keep guns out of the wrong hands. Ideally, they turn up any documented history that could indicate a potential buyer's threat to public safety. But they appear to be failing in some cases.

The implementation of firearms background checks is acknowledged by most to be imperfect, but it has its successes. Of the roughly 166 million background checks performed between 1998 and 2013, more than 1 million turned up information that prevented the purchase of a firearm [source: FBI]. In those cases, a violent felon or a stalker or someone recently released from a court-ordered stay at a mental institution went home without a gun.

Or at least that gun. After a man with a history of mental illness named John Patrick Bedell was denied a gun in California due to background-check results, he went to Nevada, which doesn't require background checks on private sales, bought a gun, and proceeded to shoot two cops in front of the Pentagon in March 2010 [source: National Law Enforcement Partnership].

While there has been a Gun Control Act since 1968 that bars certain people from owning firearms (for instance convicted felons), it was the 1981 attempted assassination of U.S. President Ronald Reagan that got an enforcement mechanism in place. An FBI department called NICS – the National Instant Criminal Background Check System – was established under the Brady bill of 1993 to enforce background checks.

The Brady Bill

James Brady (C) who was permanently paralyzed during John Hinckley Jr.'s attempt to assassinate Ronald Reagan, sits with wife Sarah and then-President Bill Clinton on the seventh anniversary of the Brady bill in 2000.
James Brady (C) who was permanently paralyzed during John Hinckley Jr.'s attempt to assassinate Ronald Reagan, sits with wife Sarah and then-President Bill Clinton on the seventh anniversary of the Brady bill in 2000.
© Ron Sachs/CNP/Sygma/Corbis

In 1981, John Hinckley Jr. tried to assassinate Ronald Reagan to win the attention of actress Jodie Foster [source: History]. He ended up shooting several people, including the president, a Secret Service agent, and then-press secretary James Brady, who was critically injured in the attack and would be in a wheelchair from that point on.

The year before, Hinckley had been arrested for stalking President Jimmy Carter [source: National Law Enforcement Partnership]. The Brady Handgun Violence Prevention Act, or "Brady bill," called for background checks – which presumably would have turned up Hinckley's past arrest – before all handgun purchases. After years of campaigning by proponents, the law was passed by Congress in 1993, and it went into effect in 1994.

The Brady bill established three major changes in gun regulation, and the first two were immediately implemented. Beginning in 1994, federal law called for mandatory background checks and a five-day waiting period for all gun purchases from federally licensed gun dealers (or FFLsFederal Firearms Licensees). This was before most criminal records were easily accessible in centralized computer databases, and the waiting period was designed to give the FBI enough time to search [source: National Law Enforcement Partnership].

The third key point in the Brady bill called for the development of the National Instant Criminal Background Check System that we just mentioned. The NICS, a department of the FBI, would be the central processing point for all of those pre-purchase background checks, with the ability to tap into multiple sources electronically. When NICS went online in 1998, checking backgrounds became a quicker process, and the federal five-day waiting period was dropped [source: National Law Enforcement Partnership].

Since then, the time it takes to conduct a basic firearms background check has decreased. NICS can search both state and federal criminal records and return a response in about 30 seconds. The whole process starts with the potential buyer filling out a rather succinct ATF Form 4473.

Performing a Background Check

A customer walks into a licensed gun store and chooses the model(s) to purchase. Before any money changes hands, he or she fills out ATF Form 4473, which in addition to asking for name, address, citizenship and other basic information, will ask whether the buyer has been convicted of a crime with imprisonment of more than one year; is a fugitive from justice; is addicted to drugs; judged mentally defective; or unlawfully living in the U.S., among other criteria.

Once the form is filled out, the gun dealer then either picks up the phone or goes online to reach the NICS division at the FBI, or a state agency that acts as an NICS "Point of Contact" (POC) and has access to the FBI system. A licensed gun dealer in a POC state contacts the state agency instead of the FBI [source: FBI].

The dealer submits the supplied Form 4473 responses. The NICS searches for records matching that potential buyer with any of the prohibited criteria listed on the form. The system automatically searches three databases:

  • Interstate Identification Index, a nationwide database of criminal records
  • National Crime Information Center, a nationwide database of restraining orders and outstanding warrants
  • NICS Index, a supplemental database of people identified by state and federal sources as ineligible to purchase a gun, including people in the United States illegally and those with documented mental illnesses that would indicate a threat to public safety.

If the potential gun buyer is not a U.S. citizen, the search extends to databases maintained by the U.S. Immigration and Customs Enforcement agency [source: Bureau of Justice Statistics].

In less than a minute, the gun dealer receives one of three responses: "Proceed" with the sale, indicating no matches were found; "deny" the sale, indicating at least one definitive match; or "delay" the sale, indicating at least one possible match [source: FBI].

With a "delay," the clock starts running on a three-day waiting period. The FBI has exactly 72 hours to gather additional information from sources not automatically searched by the NICS, which can include contacting state or local law-enforcement or court authorities directly. If the FBI can confirm the match, a "deny" response is returned to the gun dealer; if the FBI can disprove the match, a "proceed" response is returned; and if the FBI is unable to do either (or just doesn't respond) by the end of the three days, it is within the gun dealer's discretion whether or not to proceed with the sale [source: FBI].

Regardless of the response, the FBI must destroy all records generated by the background check within 24 hours of returning a decision. The only exception to this is the Voluntary Appeal File (VAF). The gun seller is not told the reason for the "deny" and so cannot tell the prospective buyer. But the denied person can find out by writing to the FBI or state POC. He or she can also file an appeal, in which case the FBI reviews its decision in light of any additional information or corrections provided by the denied buyer. If the appeal is granted, the sale can proceed [source: FBI].

The system seems pretty straightforward. And yet, there are some serious limitations.

Database Limitations and HIPAA

While NICS is a federally implemented system, its effectiveness relies heavily on state participation. State compliance in supplying records varies, partly because not all states have achieved fully computerized record-keeping. Since 2008, with the passage of a Brady bill amendment in the wake of the 2007 Virginia Tech massacre, the federal government has increased funding for states to digitize their criminal records. Since then, database submissions have increased [source: FBI].

But certain types of records are widely withheld. That amendment, the NICS Improvement Amendments Act (NIAA), was most notably aimed at increasing the provision of mental health records not generated by court proceedings. The 2007 Virginia Tech shooter had a documented history of mental-illness-related hospital visits, including a night spent in a psych ward, that didn't show up in the background check performed before he legally purchased the guns he used to shoot 32 people and himself [source: Friedman].

But the goal of expanding the mental-health records available to NICS is complicated by another, older act: the 1996 Health Insurance Portability and Accountability Act, or HIPAA. Part of HIPAA protects the privacy of patient medical records, limits who has the right to see them, and gives patients greater control in deciding who's allowed to access their histories [source: U.S. Dept. of Health & Human Services].

In some specific cases, HIPAA allows for health information to be released to law-enforcement authorities without the patient's consent -- records indicating child abuse or domestic violence, the location of a fugitive of justice, or elements of a crime, for instance [source: U.S. Dept. of Health & Human Services].

Firearm background checks are not among HIPAA's list of privacy exceptions, and states decide for themselves whether to allow NICS access to protected mental-health records. The NIAA seeks to increase provision of mental-health-related records by tying them to federal funding of state law-enforcement activities. Some states have responded by feeding more health records into the system. Others have deferred to HIPAA and still keep them private. In 2012, a federal review showed 17 states had contributed less than 10 mental health records to NICS [source: Pickler].

The absence of comprehensive mental-health records in the NICS places significant limits on the efficacy of background checks; but of the 100,000 annual gun-related casualties in the United States, relatively few of them are at the hands of mentally ill mass-murderers. There's a far greater loophole in the background check system.

The "Private Sale" Exception

Hundreds attend a gun show in Fort Lauderdale, Fla. Background checks are not required at gun shows.
Hundreds attend a gun show in Fort Lauderdale, Fla. Background checks are not required at gun shows.
© Roy Morsch/Corbis

Perhaps the greatest factor crippling the background-check system in the United States is right there in the Brady law: Mandated background checks apply only to Federal Firearms Licensees.

FFLs were established in the Gun Control Act of 1968, which required anyone in the "business" of selling firearms (through retail store or pawnshop) be licensed by the federal government. With that license comes the background-check requirement.

Those who are not in the "business" of selling guns need not obtain a license, and therefore need not perform background checks. This can include people who sell guns occasionally at gun shows, where stalls may display a "private" sign to let potential buyers know there will be no background check performed [source: Kirkham].

Guns sold online, or to a friend living down the street, are also in the "private" category. Only about 25 percent of U.S. states require background checks or record keeping for at least some private sales [source: Kirkham]. A whopping 40 percent of all gun transfers fall into the private sale category [source: National Law Enforcement Partnership]. A Bureau of Justice Statistics survey of prison inmates found that 80 percent of those who'd used a handgun in their crimes got them through a private transfer.

These "private sale" exceptions are likely the greatest hindrance to the effectiveness of the background-check system. Numerous pieces of federal legislation have attempted to make background checks universal in the United States, all failing to make it out of Congress. This is typically attributed to objections by the politically powerful National Rifle Association, or NRA.

The organization's leadership believes expanding background checks would affect only law-abiding citizens and would ultimately lead to the formation of a federal gun registry, enabling government confiscation or increased taxation of legally owned guns. They point out that the same inmate survey showed less than 2 percent got their guns from a gun show or flea market. Most got their guns from "friends or family" or from "the street/ illegal source" (e.g. by theft) – all of which were counted in the private transfer number [source: NRA-ILA].

After the Newtown, Conn., school shootings in 2012, one poll showed 91 percent of American voters and 88 percent of gun owners favored background checks on all gun sales, including private ones [source: Schoen]. In 2013, yet another bill was introduced to accomplish that and voted down by the Senate [source: McAuliff].

For the time being, that leaves universal background checks in the hands of the states, and evading one a simple matter of crossing state lines to find an unregulated private sale. Or else going to the black market. Though many don't see what the difference is at this point.

Author's Note: How Firearm Background Checks Work

When explaining a "conversation" as socially and politically divisive as gun control, a writer is faced with a lot of decisions along the way in the interest of objectivity. I made every effort to stick to the facts and relied heavily on statistics from primary sources like the FBI and the ATF. Doubtless, some readers will read a bias, one way or another. Some don't necessarily trust the FBI and ATF to provide accurate statistics in the first place. Those were my best options, though, and so I went with it. Numbers are notoriously difficult to pin down, so view all counts and percentages as estimates.

Related Articles


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  • ATF. "Brady Law." (April 30, 2013)
  • ATF Form 4473. (April 23, 2013)
  • ATF. "Permanent Brady Permit Chart." April 26, 2011. (April 22, 2013)
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