A three-judge panel of the 4th U.S. Circuit Court of Appeals issued its unanimous ruling Friday. The panel rejected several claims by Muhammad, including that he never should have been allowed to act as his own lawyer for part of his 2003 trial because he was too mentally impaired.

The 2002 shootings by Muhammad and teenage accomplice Lee Boyd Malvo terrorized the Washington, D.C., area. In all, 10 people were killed in four states, including Alabama and Louisiana, before the pair moved on to Virginia, Maryland and D.C.

Muhammad's attorney, Jonathan Sheldon, said in an e-mail that he will appeal to the U.S. Supreme Court.