Lawyers for death-row inmate Damien Echols asked Arkansas` highest court Thursday to order a hearing on whether the condemned man was mentally competent when convicted of killing three boys. Echols was sentenced to die for the May 1993 bludgeoning deaths of three eight-year-old West Memphis boys. Defense lawyer Robert Owen of Austin, Texas, says Echols should get a hearing on his mental competency. Assistant Attorney General David Raupp said such a request should be barred because Echols` mental health was not raised in the inmate`s previous appeals. Owen also argued that the condemned man`s trial lawyers, Val Price and Scott Davidson of Jonesboro, failed Echols by entering a contract with H-B-O three weeks into the trial and staging a strategy session for filmmakers. Assistant Attorney General Jeff Weber said there was no conflict of interest in the H-B-O filmmaking because Echols himself signed the contract. Second-graders Steven Branch, Michael Moore and Christopher Byers disappeared May fifth, 1993, while riding bicycles in their quiet, tree-lined neighbor in West Memphis. Their bodies were found the next day in a watery ditch near their homes. Echols, Jason Baldwin and Jessie Misskelley, all teenagers at the time, were convicted in the murders. Echols was the only one sentenced to death. Baldwin is serving life without parole and Misskelley was sentenced to life in prison plus 40 years.