How the ban came about
Soon after the Las Vegas shooting, President Donald Trump vowed to outlaw bump stocks.
But some lawmakers and gun lobbyists resisted, making new legislation unlikely. That made a regulatory change the only realistic path to accomplishing Trump's goal.
At his direction, the Justice Department in March 2018 proposed a rule clarifying that bump stocks were not merely parts but instead were "machine guns" -- what the federal government calls fully automatic weapons -- as defined by existing law.
Why? Because "such devices allow a shooter of a semiautomatic firearm to initiate a continuous firing cycle with a single pull of the trigger," similar to automatic rifles, the department said.
Defining bump stocks as machine guns effectively bans them. Civilian possession of fully automatic weapons was outlawed in 1986 except for those already lawfully in people's ownership.
After considering public comments about the proposal, the department finalized and published the rule on December 26.
And there is no grandfather clause for bump stocks, the new rule says, because they weren't manufactured until well after the 1986 law went into effect.
Some gun-owner advocacy groups
sued the Justice Department, asking federal courts to prevent the ban. In one case, a judge in February
rejected plaintiffs' arguments that the Justice Department violated procedural requirements, and that the official who signed the rule, Matthew Whitaker, then the acting US attorney general, did not have authority to do so.
The Supreme Court received two emergency appeals Monday night. In one of the cases, which had been before the US Court of Appeals for the D.C. Circuit, Chief Justice John Roberts declined an emergency request to put the ban on hold.
In another case out of the 6th US Circuit Court of Appeals, Gun Owners of America and other individuals are asking for a stay, arguing the final rule "reverses well over a decade of consistent ATF classification of bump stocks as unregulated firearm accessories." Justice Sonia Sotomayor, who has jurisdiction over the 6th Circuit, asked the Trump administration for a response by 4 p.m. Tuesday.
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