West Virginia’s congressional delegation joined more than 200 members of Congress in backing a court challenge to the U.S. Environmental Protection Agency’s carbon-cutting Clean Power Plan.

In a brief filed Feb. 23 with the U.S. Court of Appeals for the District of Columbia Circuit, 34 senators and 171 representatives argue the EPA overstepped its boundaries in creating the rule. Sen. Joe Manchin, D-W.Va., who is the only Democrat listed on the brief, signed on along with the rest of West Virginia’s Republican-led delegation, which includes Sen. Shelley Moore Capito, and Reps. Evan Jenkins, David McKinley and Alex Mooney.

“… (The) Final Rule seeks to transform the nation’s electricity sector by setting carbon dioxide (‘CO2’) emission reduction mandates for the States. Congress never authorized EPA to compel the kind of massive shift in electricity generation effectively mandated in the Final Rule,” the brief states.

The lawmakers went on to say the rule goes “well beyond the clear statutory directive.”

“In reality, if Congress desired to give EPA sweeping authority to transform the nation’s electricity sector, Congress would have provided for that unprecedented power in detailed legislation. Indeed, when an agency seeks to make ‘decisions of vast economic and political significance’ under a ‘long-extant statute,’ it must point to a ‘clear’ statement from Congress,” the brief continued, citing a 2014 opinion authored by the late U.S. Supreme Court Justice Antonin Scalia in a prior case regarding EPA’s authority to regulate greenhouse gases under the Clean Air Act.

The motion comes about two weeks after the U.S. Supreme Court ruled the EPA can’t begin enforcing the rule until legal challenges filed by 25 states, including West Virginia, and four state agencies are resolved.

The D.C. Circuit Court of Appeals will hear oral arguments on the merits of the states’ case on June 2.