Who gets a gun?

Universal background checks for gun buyers are at the center of President Obama’s proposed gun-control agenda. This is a valuable reform that closes gaping loopholes in our current partial background check system. Yet, to be both effective at reducing crime and respectful of Americans’ 2nd Amendment rights, the president’s proposal falls short in two ways.

Backgrounds checks should be truly universal. And they should be free.

Under current law, a gun purchaser must submit to a background check whenever he or she buys a gun from a federally licensed gun dealer. The process is simple. The gun dealer runs the buyer’s information through a computer database maintained by the federal government, which usually returns an answer within minutes, if not sooner. It’s not a significant burden on buyers, save for the felons and people adjudicated to be mentally ill (“prohibited purchasers”) who are rejected.

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You don’t need to be a gun dealer, however, to sell a gun. Unlicensed (or private) sellers — people who aren’t ordinarily in the business of selling firearms — can sell firearms without having to conduct background checks. This is the source of the so-called gun show loophole, which is a misnomer; there are no special rules for gun shows, but they are handy places for people who don’t want to submit to a background check to buy guns.

In fact, the loophole is much broader than gun shows. A private seller can sell a gun through classified ads, a yard sale or in the parking lot of a shooting range. Anywhere from 15% to 40% of lawful gun sales are private, with no background checks. Obama’s proposal aims to close this gap.

Yet, the president’s plan does not go far enough.

In a bow to the gun lobby, Obama has endorsed an exception to universal background checks for transfers of firearms within families. The argument is that a father who wants to pass on to his son a beloved rifle shouldn’t be burdened by having to conduct a background check. And family members, who are most at risk, should have every incentive to refuse to give a felon or dangerously mentally ill person a gun.

The data, however, suggest the opposite. It’s precisely those closest to a prohibited purchaser we should trust the least. In studies of prison inmates, nearly 35% obtained their guns from friends and family members — the largest single source of criminals’ guns.

Studies also show that many “straw purchases” — in which a person buys a gun on behalf of a person who cannot legally do so — are made by spouses, girlfriends and other close friends. Personal relationships often make it difficult for someone asked to buy a gun to say no.

Every gun transfer, including those within families, should require a background check. No exceptions. No loopholes.

The president’s proposed background check policy should also include an additional reform: All background checks should be free.

In states such as California that already mandate background checks for private sales, buyers and sellers have to go to a licensed dealer for the check. Dealers, who don’t much like the hassle of completing a sale they won’t otherwise profit from, typically charge upward of $35 for the service.

Out of respect for the 2nd Amendment, Congress should outlaw such charges and require dealers to conduct background checks as a condition of maintaining their licenses. The background check fee is similar in effect to a poll tax on voting. Both prevent some subset of people who wish to exercise their rights from doing so — often the poorest Americans, who are disproportionately minorities.

And although poll taxes, unlike background checks, were a product of racism, the basic point remains: Individuals should not be required to pay unnecessary fees to exercise a constitutional right.

By making background checks truly universal and free, Congress can please both sides in the gun debate. Lawmakers would be doing more to keep criminals from obtaining guns while still respecting the 2nd Amendment.

Adam Winkler is a professor at UCLA School of Law and the author of “Gunfight: The Battle over the Right to Bear Arms in America.”