A federal appellate court has dismissed the appeal of a man who was sentenced to death for kidnapping, torturing and killing a young northern Idaho boy after killing several members of his family.

Joseph Edward Duncan III faces the death penalty for the 2005 murder of 9-year-old Dylan Groene. He also faces several life sentences for the murder of three family members and the kidnapping of his then-8-year-old sister.

Duncan represented himself at his sentencing hearing and later waived his right to appeal. But he has since changed his mind and his defense attorneys say he wasn't mentally competent to waive his rights.

On Friday, the 9th U.S. Circuit Court of Appeals rejected that claim. The court said a lower court had correctly found Duncan competent. The justices said it was too late for Duncan to change his mind.