A federal judge denied an injunction request to stop President Donald Trump's ban on bump stock firearm accessories from taking effect on Monday, saying the gun rights groups opposing the rule failed to make their case.

What's the background?

The term "bump stock" became a part of the American vernacular after the device was used in a horrific 2017 mass murder at a country music festival in Las Vegas. Immediately, there were calls for banning the accessory, which is used to simulate the effect of automatic fire on semi-automatic weapons.

In response, the Bureau of Alcohol, Tobacco, Firearms and Explosives reclassified the devices as "machine guns" — which are banned in the U.S. — and issued a directive requiring any citizens who owns a bump stock to either destroy it or hand it in to federal authorities before March 26.

Several gun rights groups organized to fight the ban in court, arguing that the rule infringes on Americans' Second Amendment rights.

What's the deal with the injunction?

In Monday's ruling, U.S. District Judge Dabney Friedrich in the District of Columbia issued the decision against the plaintiffs, which included the Firearms Policy Coalition.

The FPC and its co-plaintiffs in the case say the Trump administration's proposed ban is illegal, arguing the rule issued by the ATF is unconstitutional on several grounds and — among other things — "exceeds its statutory authority."

FPC also argued that previous acting Attorney General Matthew Whitaker — who signed the order — did not have the authority to take such an action as a temporary administration official.

In her 64-page decision, Judge Friedrich said the plaintiffs arguments against the ban were not "persuasive," and denied their motions seeking a preliminary injunction of the rule.

Anything else?

The Gun Owners of America have filed a separate request for a preliminary injunction against the bump stock ban in Michigan, and a hearing on the case is scheduled for March 6.

According to the GOA, as of last week there were four cases against the ban pending in three circuit courts. The GOA plans to take its case all the way to the U.S. Supreme Court, if necessary.