WASHINGTON (CN) — Renewing his administration's focus on American gun violence, President Joe Biden announced a series of measures Monday targeting "ghost guns" and a new nominee to head the federal agency that investigates traffickers.
The term "ghost guns" is used to encompass do-it-yourself firearms that can be bought in pieces over the internet and assembled at home. Individual gun components lack serial numbers, however, making them impossible for law enforcement to track and trace.
"Many are sold without a background check. They're accessible to almost anyone. They often come in kits— bought online —that can be assembled quickly with little or no training. That means that someone can convert parts in a box into a working gun with alarming ease," U.S. Deputy Attorney General Lisa Monaco said during the announcement Monday.
By expanding the definition of firearms under the Gun Control Act to include self-assembly kits, manufacturers will now have to license themselves as firearm producers and label the kit components with serial numbers.
Commercial sellers will have to also carry a federal license to sell ghost gun kits and must conduct background checks before selling them to consumers.
These new changes will also retroactively target self-assembled guns already on the market, with the Department of Justice mandating dealers with federal licenses to add serial numbers to any unlabeled guns in their possession before selling them.
Under the new rules, firearms dealers will also have to maintain records until they go out of business or stop federally licensed gun sales. Previous laws required sellers to maintain records for 20 years, after which point they were allowed to destroy their records tracking the sale of firearms.

The National Tracing Center, a branch of the Bureau of Alcohol, Tobacco, Firearms and Explosives, estimates that an average of 1,300 firearms a year become untraceable because dealers destroyed records that were more than 20 years old.
While gun control legislation has struggled to gain momentum in Congress, Biden chided lawmakers and gun lobbyists for not backing gun regulation reforms.
"It's not extreme, it's just basic common sense," Biden said.
"We need Congress to pass universal background checks. And I know it's controversial, but I got it done once — ban assault rifles, " the president added, referencing the 1994 assault weapons ban that lapsed during the Bush administration.
Biden also on Monday announced the nomination of Steve Dettelbach, a former U.S. attorney for the Northern District of Ohio, to direct the Bureau of Alcohol, Tobacco, Firearms and Explosives, which has not had a permanent leader since 2015.
The president originally wanted the job to go to David Chipman, a leader at former Representative Gabby Giffords' anti-gun violence organization, but pushback from Republicans and moderate Democrats tanked Chipman's nomination.
"This is an agency whose mission is to protect communities from violent criminals, illegal trafficking of firearms, act of arson and bombing and a lot more. The mission of this agency isn't controversial, it's public safety," Biden said, alluding to the difficulty presidents have had in recent years securing a director for the agency.
Presidents from both parties have failed to confirm nominees to the position since it became a role requiring Senate approval in 2006.
Dettelbach was unanimously confirmed to his Ohio post by the Senate back in 2009.
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