The Supreme Court Thursday threw into doubt the fraud convictions of former Enron Corp. Chief Executive Jeffrey Skilling and ex-media baron Conrad Black, a setback for the U.S. Justice Department in two of the biggest corporate fraud prosecutions of the last decade.

 

The high court limited the reach of a federal fraud law that Justice Department prosecutors have used in a number of cases alleging public corruption by government officials and fraud by executives like Black and Skilling.