Column: Trump once said we should enforce existing gun laws. Will he keep his promise?

When he ran for president last year, Donald Trump said we didn’t need any new laws restricting guns. Instead, we should simply enforce laws already on the books.

“We need to fix the system we have and make it work as intended,” Trump’s campaign website said. “What we don’t need to do is expand a broken system.”

This would be a good time for him to deliver on that campaign promise.

Devin P. Kelley, the gunman who killed 26 churchgoers in Sutherland Springs, Texas, on Sunday, should never have passed the standard federal background check administered by licensed gun dealers. In 2012, Kelley was convicted in a military court for assaulting his then-wife and fracturing the skull of her young child.

But the U.S. Air Force failed to enter Kelley’s 2012 conviction into the federal database used for background checks — so he was able to purchase three firearms from gun stores by claiming he knew of no reason that he should be disqualified.

It’s not clear whether the Air Force has been reporting domestic violence misdemeanors to the FBI database at all. A Defense Department website says only one such case has been reported — from all of the armed services put together.

If it turns out that the armed forces haven’t been reporting most domestic violence convictions, that could include thousands of cases. And that lapse is symptomatic of a much broader problem with the background check system: The FBI database relies on a hodgepodge of other agencies for its information. It’s only as reliable as the records they provide — which means it often isn’t reliable at all.

Kelley’s case isn’t the only time the system didn’t work as intended.

In 2015, Dylann Roof, a 21-year-old white supremacist from Columbia, S.C., was allowed to buy a .45-caliber handgun even though he had admitted to felony drug possession, a crime that should have disqualified him. The record of his conviction hadn’t been submitted to the FBI by local police agencies. By the time the bureau discovered his conviction, more than 72 hours had passed, the deadline for denying a sale. Last December, Roof was convicted of killing nine people at a prayer service at a historically African American church in Charleston.

In 2007, Seung-Hui Cho, a 23-year-old student at Virginia Tech, bought two handguns even though a local judge had ruled him to be mentally ill, yet another determination that should have disqualified him from owning a firearm. But Virginia authorities never submitted his court records to the FBI, so he passed two background checks. In April 2007, Cho killed 32 people and wounded 17 others on the Virginia Tech campus before killing himself.

The Virginia Tech shooting prompted Congress to pass a law encouraging states to report mental health data, and many states responded. That part of the system has improved. But the picture isn’t as encouraging when it comes to domestic violence, the crime Kelley committed.

Federal law prohibits sales by firearm dealers to anyone convicted of a domestic violence charge or under a judicial restraining order for threatening a spouse, with some exceptions. Last year, the Government Accountability Office found that while most states reported domestic violence misdemeanors and protection orders to the FBI, their performance was uneven.

“Some states are not submitting records at all for technical reasons,” said Elizabeth Avore of Everytown for Gun Safety, an organization that promotes gun control. “Others are submitting records, but without enough detail.” The GAO report didn’t identify which states are falling short.

Instead of strengthening enforcement, though, the Trump administration has been rolling back regulations. In February, President Trump signed a bill prohibiting the Social Security Administration from reporting mentally impaired recipients to the FBI database, reversing an action by President Obama. According to Avore, the new law means as many as 443,000 mentally impaired Social Security clients can now pass background checks for gun purchases.

At the same time, the Justice Department issued a new guideline that could allow more people with outstanding arrest warrants to buy guns. The new rule says the FBI can block a gun purchase only if a fugitive has fled across a state line to avoid prosecution or to avoid giving testimony in a criminal case. (The previous rule covered all fugitives who crossed state lines.)

And Trump has proposed cutting the budget of the Bureau of Alcohol, Tobacco, Firearms and Explosives, the main federal agency enforcing gun laws, by 14% over the next decade.

To put a serious dent in our epidemic of gun violence, we need new laws, beginning with expanded background checks to cover purchases from sellers who aren’t licensed gun dealers. In many states, felons and others have an easy time buying guns, because “private” sales don’t require background checks at all.

A Pew Research Center poll last year found that 83% of Americans favor such laws, including 75% of people who described themselves as Trump supporters.

But for those who say we should merely enforce the laws already on the books, the tragedy in Sutherland Springs should serve as an incentive to make the system work — as candidate Trump proposed.

doyle.mcmanus@latimes.com

Twitter: @DoyleMcManus

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