CHICAGO (CBS) — Lawmakers are hoping to close a loophole that allowed the Aurora shooter who killed five coworkers on the job to get his hands on a gun and keep it.

Illinois State Police said Aurora shooter Gary Martin slipped through the cracks by lying on his application for a FOID card, and because Illinois does not have a fingerprinting requirement, the system missed his 20-year-old conviction for stabbing a former girlfriend in Mississippi.

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Martin killed five coworkers before he was killed in a shootout with police.

“I think that shooting pointed out a gap in the law, and it’s a gap that we can easily fix,” said Laura Singer, of Moms Demand Action.

Singer is one of the moms who boarded a bus for Springfield Wednesday morning to support Senate Bill 1966, which would require finger printing and increase FOID fees from $10 to $50, a pretty rigorous requirement compared to other states.

Only a handful like Hawaii and Florida require fingerprints at the state level.

But David Chapman, who spent 25 years with the Bureau of Alcohol, Tobacco, Firearms and Explosives, said that ultimately fingerprints are hard to fake.

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“Fingerprints are the standard,” he said. “And for a state that has experienced things that they don’t want to ever happen again, this makes sense.”

Chapman said it could help limit the number of FOID cards that are issued in error, like in the Aurora case.

According to data obtained by CBS 2, in 2018 3,429 cards were revoked in Cook County, but 39% of those cards were never actually returned.

It’s even worse where Gary Martin lived in Kane County where 41% of cards went unreturned.

Meanwhile the executive director of the Illinois State Rifle Association spoke to CBS 2 from Springfield, where his organization is threatening to take the bill to court if it’s passed into law.

“How much more do they want from us?” said Richard Pearson. “It’s also an impediment because it’s quite expensive, particularly in southern Illinois. You have to go a long way that will fingerprint you.”

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The “Fix the FOID” Act passed out of committee Tuesday. It is poised for a vote in the House. The Senate would have to sign off before it goes to the governor’s desk.

Megan Hickey