The U.S. Supreme Court halted the execution of a Prince William County man who was set to die tonight so the justices could consider whether to hear arguments that Paul Warner Powell was unconstitutionally tried twice for killing a 16-year-old Manassas girl.

The order came as Virginia corrections officers were practicing electric chair procedures for the 31-year-old Powell, who in 1999 drove a knife into the heart of teenager Stacie Lynn Reed before raping and stabbing her 14-year-old sister, Kristie.