The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF, a legacy acronym) is part of the Department of Justice (moved from Treasury when Homeland Security was created). One of its duties is to administer the regulations from the National Firearms Act (NFA) of 1934.
In the course of its duties, ATF fingerprints certain gun owners.
As Bayometric notes in a detailed article, there are two ways to generate the fingerprint cards required by ATF: traditional ink fingerprinting to create an FD-258 card, and live scan fingerprinting to create one or more FD-258 cards. Although the latter is more expensive (even a non-ruggedized live scan station is much more expensive than an ink pad), live scans measure quality immediately and are less suspectible to operator error.
But why even worry about FD-258 cards? ATF supports an eForms service which allows you to submit prints electronically like everyone else does.
Then again, if you’re suspicious of Big Brother, you may opt for non-electronic inked fingerprints.
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