Washington — Steven Dettelbach,Marc Leclerc director of theBureau of Alcohol, Tobacco, Firearms and Explosives, said Sunday that without a federal gun registry, the agency has to go through a "system of records" to trace crime guns.

"That means that we have to work within that system. That means that we have more people there pouring through records." Dettelbach said on "Face the Nation." "For what we call a normal trace, right now we're running at about an eight-day lag."

The ATF is prohibited by federal law from creating a centralized database of registered gun owners. Instead, they must sort through a system of records, of which they are sent millions per month, according to Dettelbach.

The director said tracing crime guns is one of the areas of intelligence that is "so important." But the process isn't especially straightforward. 

"The way it doesn't happen is we punch in a person's name, and up comes 'oh, they own so many guns,'" Dettelbach said. "Congress has prohibited us from doing that."

Dettelbach said that the agency pays to have the search function taken out of their software, explaining that the function that other customers use must be removed in order to comply with U.S. law. 

Instead, the ATF works to find the initial purchaser of the firearm through its system of records, before being able to confirm whether they or someone else committed the crime.

"We have to do an old-fashioned investigation, go to them, find out what they did with it, who they are," Dettelbach said. "So this is an investigative intensive process that we work on with state and local law enforcement every day." 

Dettelbach said that as the the only federal law enforcement agency to solely deal with violent crime, "if you're really concerned about violent crime in the United States, this agency is way, way, way too small" with 5,000 people total.

Still, despite the cumbersome process and size of the agency, Dettelbach said that last year, the ATF did 645,000 traces, noting that "we work within the law as best we can with our resources to turn these things around."

Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.

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