A federal appeals court on Tuesday ordered a new sentencing hearing for convicted police killer and death-row activist Mumia Abu-Jamal, finding for a second time that the death-penalty instructions given to the jury at his 1982 trial were potentially misleading.

The 3rd U.S. Circuit Court of Appeals told prosecutors to conduct the new sentencing hearing within six months or agree to a life sentence. Abu-Jamal's first-degree murder conviction still stands in the fatal shooting of Officer Daniel Faulkner.

District Attorney Seth Williams said he would consider mounting another appeal to the U.S. Supreme Court.

Defense lawyers for the former Black Panther, meanwhile, said the ruling addresses "an unfortunate chapter in Pennsylvania history."

"Pennsylvania long ago abandoned the confusing and misleading instructions and verdict slip that were relied on in Mr. Abu-Jamal's trial in order to prevent unfair and unjust death sentences," said Widener University law professor Judith Ritter, who argued the most recent appeal in November. "Mr. Abu-Jamal is entitled to no less constitutional protection."