SAN FRANCISCO (KPIX 5) — Guns do not belong in the hands of mentally ill people. Mass shootings in the past few years prove that. But in California — despite strict gun control laws — tens of thousands of people with mental illness are packing heat.

Barbara Alexander can never forget the call she got about an armed standoff involving her son.

“He was in a parking lot, in a public place. They sent the swat team, helicopters came up, it was quite horrifying,” she said.

‘Horrifying’ because her son, now an adult in his 40’s, has been hospitalized many times for severe mental illness. Mental illness is an issue in many mass shootings, including most recently with Navy Yard shooter Aaron Alexis.

Mentally ill people are not allowed to buy guns in California. But Barbara says her son was able to buy several of them, including at least one semi-automatic rifle, from a gun store in Sacramento.

“I was horrified. Because those are the last people you want to have weapons,” she said.

It’s not an isolated case. According to a state audit, the Department of Justice is behind on identifying people with mental illness and cross-checking them in what’s called the Armed Prohibited Persons database.

“They have a backlog,” said Margarita Fernandez with the state auditor’s office. She says the audit found 380,000 current gun owners that have still not been reviewed. “They started out, I believe they had a million. So they have actually gotten down to 380,000.”

Not only that, the DoJ is not even keeping up with hundreds of new firearm purchases made every day. “They get behind on the daily, and then they have to do them the next day,” Fernandez said.

That means that despite background checks meant to prevent mentally ill people from buying guns, many are still able to do so.

That’s something that shocks even gun advocates.

“If they are not doing that in a timely matter, then that is severe negligence,” said Jay Jacobson. He owns a rifle factory in Morgan Hill and says that kind of poor bookkeeping would shut his place down.

“I have thousands of firearms in that vault and I have to account for every one of them like they were each one of my children. If one of them goes missing god forbid,” he said.

It’s a double standard that he thinks the Department of Justice should be held responsible for. “Someone needs to get fired and if Ms. Harris can’t find out who is responsible, then I think she ought to be recalled,” he said.

We wanted to ask the state’s top cop, Kamala Harris, about this but were told her office is not commenting on the audit.

So what about Barbara’s son? He was hospitalized following the swat team incident, but is out now and no longer owns a gun. His mother, who is an active member of the Marin Chapter of the National Alliance on Mental Illness, ( http://namimarin.org ) hopes the state will take action to make sure her son can never buy a gun again.

“They need to put their resources into it, immediately. They need to start working on it now,” she said.

The Department of Justice estimates it will catch up on its Armed Prohibited Persons database by 2016. But the state auditor predicts at the going rate, it will be more like 2019.

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