Cities have doubled down on reducing emissions in recent years. Local leaders say Thursday’s 6-3 decision weakens a key federal partner that they believed would help them achieve their goals.

“Yeah, it’s a lousy bill, but it’s the best hope we have for keeping the lights on,” one lawmaker said Wednesday. 

However, the court’s use of the “major questions doctrine” indicates challenges to future regulations are likely, according to lawyers.

The plan focuses on improving efficiency and reducing emissions from buildings, the transportation sector, power generation and other sources, with the goal of achieving carbon neutrality by 2050.

The ruling issued Thursday means Congress, states and markets will drive the shift towards cleaner energy, according to Advanced Energy Economy, a trade group.