The group also estimates that more than 131,000 of the incomplete background checks that were delayed between March and May this year have been "purged."
"All uncompleted federal background check records are purged after 90 days, meaning that most of the delayed records from March through May - an estimated 131,000 - are now lost forever," it says.
Rob Wilcox, deputy director of policy and strategy at Everytown for Gun Safety, told Reuters the FBI should have "allocated the people and resources needed to conduct these background checks."
"Now, this FOIA confirms that the worst has happened: thousands of guns have likely fallen into the wrong hands due the Charleston loophole, and there's no end in sight," Wilcox said in a news release.
Gun reform advocates have pushed for closing the loophole while gun rights advocates have argued changing the law won't help fix errors such as the one that allowed the Charleston shooter to purchase a gun, The State previously reported.
A bill that targeted the Charleston loophole passed in the U.S. House in February 2019, The State reported, but the Senate has never voted on it, per The Hill.
The House also passed a fiscal year 2021 Commerce, Justice, Science and Related Agencies appropriations bill that included provisions that called for data related to the loophole and actions on gun regulations.
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