By: David G. Savage

The justices, by a 5-4 vote, issued an unusual emergency order that blocks theEnvironmental Protection Agency from moving forward with its effort to reduce carbon pollution from power plants by 32% by 2030.

The court’s order said the EPA’s “carbon pollution emission guidelines” for power plants are “stayed pending” a decision from the U.S. Court of Appeals in Washington, which will hear the case this summer.

It is rare for the high court to intervene in a case pending in the lower courts. The brief order suggests that most of the justices have doubts about the legality of the EPA’s policy.

Known as the Clean Power Plan, the EPA regulations would set state-by-state targets for reducing greenhouse gases from power plants. The rules would force many states to shut down older coal-fired plants and to produce more electricity using natural gas or solar and wind power.

But lawyers for West Virginia, Texas and 24 states sued, contending the EPA does not have the authority under the Clean Air Act to launch a broad attack on greenhouse gases.

They also filed an emergency appeal with Chief Justice John G. Roberts Jr. at the end of January asking for the high court to put the EPA plan on hold while their lawsuit proceeds.

The appeals court said it would hear arguments in the case in June and would probably rule in the fall, during Obama’s last months in the White House.

The president’s order had urged the justices to turn down the emergency request, calling it “extraordinary and unprecedented.”

Meanwhile, 18 mostly Democratic-led states, including California and Illinois, filed a brief supporting the administration.