A Bay Area ABC affiliate reported late Tuesday that the gun used in the July 1 shooting death of 32-year-old Kathryn Steinle on San Francisco’s Pier 14 was allegedly issued to a U.S. Bureau of Land Management agent and later stolen from the agent’s car. Somehow, the gun landed in the hands of Juan Francisco Lopez-Sanchez (he claims he found the gun wrapped in a T-shirt), a Mexican immigrant who has been deported five times, convicted of felonies seven times in the U.S., and now faces murder charges.

The shocking crime has generated headlines across the country. While law enforcement continues to investigate, here are four things to know about gun theft and related laws:

How common is it for a gun to be stolen from a car?

There’s no comprehensive survey of gun thefts across the country, but law enforcement officials say that guns left in cars are prime targets for thieves.

As The Trace reported in June:

In the spring of 2013, in advance of opening day at Busch Stadium in St. Louis, city Police Chief Sam Dotson issued a statement telling fans to leave their guns at home.

“Don’t even bring your gun down and leave it locked in your car,” he warned. “Unfortunately, there is a portion of the segment of the population that looks for people who leave their concealed carry in the car and then, in the second or third inning when people are enjoying the game, they go and break the window in the car and perhaps steal the gun.”

Two years later, the problem has only worsened, engulfing St. Louis County. In May, the St. Louis Post-Dispatch reported that in the first four months of 2015, almost 200 guns had been stolen from residents in the county — a 65 percent increase from the same period last year. Dotson reemphasized that the firearms were pilfered from parked cars more than anywhere else. “Criminals have figured this out,” he said.

Guns stolen from cars show up frequently in the database of firearms theft compiled by the Houston Chronicle in 2012. Indeed, it could be said that stealing guns from cars is something of a growth industry. Over the Fourth of July weekend, eight guns were stolen out of six unlocked cars in Jacksonville, Florida.

So if someone’s gun is stolen, do they have to report it?

It varies by state and locality. According to a 2010 study by Mayors Against Illegal Guns, only seven states and the District of Columbia require that lost or stolen guns be reported to law enforcement. (Mayors Against Illegal Guns is an earlier iteration of Everytown for Gun Safety, a seed donor to The Trace.)

California, despite its stringent gun regulations, is not among those states. San Francisco, however, requires anyone who owns or is in possession of a firearm that is then stolen to notify the SFPD within 48 hours of the firearm’s disappearance — if the owner lives in the city or the theft occurs there. The San Francisco Chronicle reports the gun was stolen in the city’s downtown. If true, it means the theft should have been reported.

But not all big cities have such laws. Seattle, another large, progressive city, is only just this week getting around to considering a law requiring the reporting of gun thefts.

In short: The lack of mandatory theft reporting is a reason it’s hard to get a handle on stolen guns.

This particular firearm belonged to a federal agent. Would his job have required that he report it stolen?

It depends on the agency. The FBI mandates that thefts of guns from personnel be reported as stolen government property. The specific policies followed by the Bureau of Land Management are unclear, but the agency did respond to The Trace’s inquiries about its rules: BLM spokesperson Jeff Krauss tells us that the agent in question reported the theft of his gun to the San Fransisco police.

UPDATE, July 9, 11:28 AM: The Bureau of Land Management responded to the Trace, clarifying its policy. When agents’ service weapons are stolen, they must notify directly local law enforcement immediately and the BLM’s own Office of Law Enforcement. The Bureau requests agents also report service weapon thefts to the FBI’s National Crime Information Center.

How often do law enforcement officials have their guns stolen or go missing?

Again, there is no comprehensive resource on the subject, but reports frequently surface of guns stolen from law enforcement officials on the local and federal level. In that rash of Fourth of July–weekend Jacksonville gun thefts from cars, two of the eight guns stolen were lifted from an FBI officer’s unlocked car, along with body armor. Even ATF officers, tasked with regulating guns, have lost possession of their government-issued firearms. The Milwaukee Journal Sentinel reported last year that ATF officers carelessly misplaced their weapons on dozens of occasions.

[Photo: Flickr user Curtis Simmons]