A parking lot in quasineutral gang territory in the Mission district was recently transformed into the staging ground for a no-questions-asked gun-buyback event. A line of vehicles stretched for several blocks, and some 30 people also showed up on foot toting armfuls of weapons.
During two hours, police collected 157 firearms, including three AR-15 assault rifles and three sawed-off shotguns — both of which are illegal. "There's only one reason to have a sawed-off shotgun, and that's to commit a crime," said one of the officers conducting the buyback.
In the wake of the Connecticut elementary school shooting in December and other similar massacres in recent years, the calls for tighter gun-control laws have become louder and gun buybacks have become more frequent. Shortly after the Connecticut incident, a buyback in the Bayview district netted 300 firearms.
However, research has shown that it's difficult to gauge the impact of such efforts, especially the buybacks.
"I know there are a lot of people that try to correlate the guns that kill people with the guns we get at gun buybacks," Police Chief Greg Suhr said. "I don't know that that is ever a consideration. It's just less guns is better than more guns."
Economist Steven Levitt's 2004 publication "Understanding Why Crime Fell in the 1990s" said gun buybacks are "largely ineffective in reducing crime." Such guns are the least likely to be used in crimes, replacement guns are easily obtained, and "the likelihood that any particular gun will be used in a crime in a given year is low," he wrote.
Firearms collected at buybacks are checked against Police Department data to determine if they are wanted in a crime; if not, they are destroyed. Those dropping them off receive $100 per gun and $200 per assault weapon.
There are an estimated 300 million guns in the U.S. and 30,000 deadly shootings annually.
Locally, a spokeswoman for San Francisco General Hospital said its trauma center has treated 1,538 gunshot victims since 2007, of whom 211 died. Victims were predominately aged between 15 and 24, male and black.
During the first six months of 2013, the Police Department recorded 175 shots fired and 91 shooting victims, about the same as during the previous year, according to data from the crime tracking program CompStat.
While the Mission gun buyback was lauded by organizers, no one can be sure what impact it will actually have in a community with a long history of gang-related gun violence.
Central American Resource Center, a nonprofit group working in the Mission since 1986, did outreach leading up to the recent buyback. The center offers removal of gang-affiliated tattoos and serves about 100 people annually.
Executive Director Lariza Dugan-Cuadra said such buybacks send a message to the community "that we don't want guns in our neighborhood."
"The question is, 'Are we getting the dirty guns or not?'" Dugan-Cuadra asked. "We don't know. We have no way of assessing that."
Supervisor David Campos combined public and private funds to pay for the retrieved guns. Officers' time was paid for by the Police Department.
Campos was dismissive of research showing such buybacks to be ineffective.
"We are talking about weapons that could be used and have been used in violent crimes," Campos said. When pressed how he could know that, he said, "I imagine there will be some that have. I know for a fact that every weapon that is turned in will not be used."
Campos said he would like to see more buyback events citywide, and eventually a program in which guns are bought back on a daily basis.
The Mayor's Office also supports buybacks as one tool to decrease violence.
"When these events get guns out of our communities, that is one less gun to mishandle, get stolen or be used on our streets," Mayor Ed Lee's spokeswoman Christine Falvey said.