Thirty years ago, the federal government identified automatic weapons for their unique ability to carry out mass casualty attacks and regulated them differently from other weapons, said Daniel Webster, the director of the Johns Hopkins Center for Gun Policy and Research. “As a result, [they haven’t] been used. Now there’s an exception to that.”
There are currently some 300 million firearms in the United States, though estimates vary. It’s legal, generally speaking, to purchase three types of guns: handguns, shotguns, and rifles. Federal law requires background checks for any transfer of a firearm between federally licensed dealers, but sales between private individuals don’t carry a federal requirement for such checks, although some states impose restrictions. Webster described it as “literally no questions asked.”
If you’re 18 years old, in most states, and aren’t otherwise barred from gun ownership, you can legally purchase a firearm from a gun show or from a seller on the internet. Eighteen states, plus the District of Columbia, have a mechanism to regulate that transaction with a background check, such as a licensing or permitting system. It’s most difficult to buy a gun in states like New Jersey and Massachusetts that have such mechanisms, Webster told me, and easiest to purchase one in states like Montana and Wyoming that do not.
For 10 years, the United States prohibited the manufacture of certain semi-automatic weapons it deemed “assault weapons,” like the AR-15 and AK-47 rifles. But that law expired in 2004. According to The New York Times, most of the firearms used in the 16 most recent mass shootings in the United States were purchased legally and with a federal background check.
Omar Mateen, who murdered 49 people at an Orlando nightclub in June 2016, used at least two legally purchased firearms, a handgun and an AR-15-style rifle. Christopher Harper-Mercer, who killed nine people at Umpqua Community College in Oregon, owned 14 guns, all of which he purchased legally. And Adam Lanza, who killed 26 at Sandy Hook Elementary School in 2012, used two rifles that were legally purchased by his mother.*
America hasn’t recently seen a mass shooting with a fully automatic weapon—which is, Webster believes, “a testament to the effectiveness of regulation.” In 1986, Congress passed a law banning the sale of fully automatic firearms, but automatics that were already in existence and registered before May 19, 1986 were grandfathered in under the law, and remain available for legal purchase by civilians. Essentially, Webster explained, “they weren’t made illegal, they simply said you can’t buy and sell new ones.”
To purchase one, a buyer must submit fingerprints, go through an FBI criminal background check, and pay a $200 tax. The guns themselves are also extremely expensive. Justin Anderson, the director of marketing at Hyatt Guns, a Charlotte-based retailer that bills itself as “America’s Largest Gun Shop,” told me that purchasing a semi-automatic weapon, like an AR-15, would cost you between $400 and $700. But for a fully automatic gun, you might spend $18,000 to $25,000. “There are a group of guys out there who buy full autos and just take them to the range to have fun,” Anderson told me, noting that machine-gun shoots happen regularly all over the country. “I’ve done it myself, it’s a lot of fun.”