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A new study from the Brady Center to Prevent Gun Violence shows that over the past two years, US gun manufacturers have ‘lost’ more than 16,000 guns.

The report, released by the Brady Center to Prevent Gun Violence, pulled data from the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) and found that 16,485 guns left the inventories of nearly 4,500 licensed gun manufacturers throughout the country without a record of them ever being sold.

In 2004 Congress passed the Tiahrt amendment – named for its sponsor then-Rep. Todd Tiahrt (R-Kansas) – which prohibited the ATF from requiring gun manufacturers to track their inventory. The Brady Campaign has long advocated for a repeal of the Tiahrt amendment.

“It is shocking that gun makers are so oblivious to public safety that they lose track of thousands of guns every year,” said Dennis Henigan, the acting president of the Brady Center. “ Given the lethality of its product, the gun industry has a special duty to act responsibly.  Instead, it has a scandalous record of carelessness.”