What gets checked in a background check?

When someone goes to a federally licensed dealer to buy a gun, they are subject to a background check through the National Instant Criminal Background Check System (NICS), a database of records that is maintained by the FBI. At the federal level, private sales are not subject to any background checks.

According to the FBI, a variety of factors in a person’s background would trigger an investigation before they could buy a gun.

If someone…

Is convicted of a crime with a sentence of more than one year

Is under indictment for a crime with a sentence of more than one year

Is a fugitive

Uses controlled substances illegally

Is determined by a court to be mentally incompetent. Importantly, just getting mental health care does not prevent you from buying a gun.

Is in the U.S. illegally

Is in the U.S. on a non-immigrant visa

Has been dishonorably discharged from the U.S. Armed Forces

Has renounced U.S. citizenship

Is the subject of a protective order against threats of domestic violence

Has been convicted of domestic violence

…then that person will be flagged by the instant check system, triggering a three-day window for the FBI to investigate further and decide whether or not a person is eligible to purchase a firearm.

Private sales, like those between friends or at a gun show, are not subject to this scrutiny. Although the specifics vary, several states require background checks for private sales, including California, Colorado, Connecticut, Delaware, Nevada, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont, Washington and the District of Columbia, according to the Giffords Law Center to Prevent Gun Violence.

Of course, if a state requires a background check for a private sale, a person can skirt the restrictions by going to a neighboring state with looser regulations to purchase a gun.

It is impossible to know whether stronger background checks work on a large scale because the data is spotty. In 1996, Congress passed the Dickey Amendment that prohibited federal funds from being used to conduct research that could inform anti-gun advocacy. The chilling effect on data about gun violence remains.

What are red flag laws?

Related to background checks, but fundamentally different in the way they are administered, so-called “red flag” laws are designed to remove guns from people deemed by a court to be at risk of hurting themselves or someone else.

Seventeen states and the District of Columbia have passed these measures, called “extreme risk protection orders,” to prevent gun violence. These are the kinds of restrictions President Donald Trump has highlighted as a way to stop mass shootings.

Depending on the state, “red flag” laws allow law enforcement, loved ones, lawyers, educators, mental health or medical providers to petition a court to take a gun away from someone deemed at risk.

There are weaknesses in the system, however. Garen Wintemute, chair of the Violence Prevention Research Program at the University of California, Davis, said the databases used for background checks are sometimes incomplete. Also, it takes time to get a court order, and the police or loved ones have to know about a gun in order to ask a judge to confiscate it.

Is there support for stronger regulation?

In the most recent poll from the PBS NewsHour, NPR and Marist, published in July, 89 percent of U.S. adults said they supported background checks at gun shows or other private sales, including 96 percent of Democrats, 84 percent of Republicans and 89 percent of people who consider themselves politically independent. Such high levels of support also came through, no matter the respondent’s age, gender, race, income and education.

In 2017, the U.S. House of Representatives passed a measure requiring universal background checks for all gun sales, but the Republican-led Senate has so far refused to vote on it. After back-to-back mass shootings in El Paso, Texas, and Dayton, Ohio, Senate Majority Leader Mitch McConnell said the issue would be “front and center” when lawmakers return to Washington in September, but he did not promise a vote on the measure. The National Rifle Association, which remains highly influential, is staunchly opposed.

Trump recently appeared to be interested in expanding background checks, and then seemed to change course, praising the current rules as “very strong.” The Associated Press reported on Wednesday that the White House has been discussing potential measures and that “meaningful background checks” are still an option.