() Days before Biden leaves office, 16 Democratic state attorneys general asked a court on Thursday to join a federal lawsuit as part of a battle to keep two Biden-era gun control policies in place.

A private gun group is challenging Biden’s ban on “forced reset triggers,” which can make a semiautomatic weapon fire like a machine gun, in the U.S. Court of Appeals for the Fifth Circuit.

Attorneys general from coast to coast, including New Jersey, Colorado, Hawaii, Illinois, North Carolina, Nevada and more, want to join the lawsuit as defendants before President-elect Donald Trump is sworn into office.

“The decision below will impose significant law enforcement and healthcare costs on Movant States and injure their quasi-sovereign interests—including in the safety of their residents,” the motion filed this week says. “And though Movant States could previously rely on federal defendants to represent their interests, the President-Elect promises to overturn the current Administration’s firearms policies swiftly.”

“Movant states” refers to the 16 state officials who want to be named defendants alongside U.S. Attorney General Merrick Garland, the U.S. Department of Justice and the Bureau of Alcohol, Tobacco, Firearms and Explosives.

A judge denied the motion the same day, meaning the states cannot become defendants in the lawsuit. But the effort signals a larger push for states to act on their interests that may clash with Trump’s before Inauguration Day.

The attorneys general also filed a motion in the U.S. District Court for the Northern District of Texas to join a lawsuit challenging the background check requirement of buyers at gun shows.

Trump, in a previous campaign speech, said he would “roll back every Biden attack on the Second Amendment.”

“We know it’s a very real likelihood, based on what the president-elect has said, that his Justice Department won’t defend these rules,” said Attorney General Matthew J. Platkin of New Jersey to the New York Times. “States like New Jersey will be harmed.”