The U.S. Supreme Court will consider Friday whether to hear an appeal from a former Ku Klux Klansman convicted in the 1964 slayings of three civil rights workers.
Court officials say a decision could be announced shortly after the conference.
Edgar Ray Killen says he was denied constitutional rights in his Mississippi trial.
Killen made the same arguments to a federal judge in Mississippi in 2012 and before the 5th U.S. Circuit Court of Appeals in New Orleans earlier this year. He lost in both courts.
The Mississippi attorney general's office did not respond to Killen's petition.
Killen is serving 60 years in prison. He was convicted of manslaughter in 2005, 41 years after the deaths of Michael Schwerner, Andrew Goodman and James Chaney.