Photo: Henry Leutwyler/Corbis

On December 8, 1980, at about 10:45 p.m., John Lennon and Yoko Ono were returning to their apartment at the Dakota when Mark David Chapman, who had earlier that day gotten Lennon’s autograph, called out his name again. “Mr. Lennon.” Lennon turned and was shot twice in the back and twice in the shoulder with a Charter Arms .38-caliber pistol.

This is that gun. Photographer Henry Leutwyler came upon it at the Forensics Investigative Division in Queens, where it’s been in police custody for 25 years (the initials scratched into the gun are thought to be those of the original forensic examiner). Most of the weapons confiscated in the city are not held on to and end up at “the burn,” where they are melted down. Others are archived: Currently, the ballistics bunker in Queens has about 800 guns, which are hung on bars, skewered through their trigger guards. But a few weapons, those that were used in significant crimes, are put on display in a bulletproof-glass case. Chapman’s .38 is on view alongside David Berkowitz’s handgun and a bazooka that was used to fire a shot at the U.N. in the sixties. But keeping this small museum going by cherry-picking the interesting weaponry out of the system requires some bureaucratic determination. “There’s this one guy, Sean, and he’s in charge of our quote-unquote library,” says a detective at the archive. He wouldn’t give his name or Sean’s last name. “Anything that we might want, he has to go down to the property clerk and, once it’s cleared, get it.” The main competition is the shooting range, where the officers want to be able to try out the prize guns.

Lennon’s murder highlighted how much New York City seemed to have declined into lawlessness. The next year, 1,867 New Yorkers were gunned down. Last week’s murder of Detective Dillon Stewart was significant in part because his is the first gun-related police death all year (in 1980, thirteen cops were shot to death). Murders in the city as a whole peaked in 1990, with a body count of 2,245. As of December 1 this year, there have been 483.

Still, that’s more than one killing a day. And it’s not as if guns are going away in the city. The ballistics department stays busy. “I’ve been here since last year,” the detective says. “I’ve personally done almost 800 cases, and there are 47 people here.”