Updated

Before John Allen Muhammad went to trial for orchestrating the deadly sniper rampage that terrorized the Washington, D.C., region, he claimed he was a prophet and that his teenage accomplice had concocted an herbal AIDS cure, his lawyers say.

Despite such grandiose statements and evidence that Muhammad's brain was damaged by childhood beatings, his trial counsel failed to stop Muhammad from acting as his own attorney for part of his capital murder trial, his new legal team has argued in briefs filed with the 4th U.S. Circuit Court of Appeals.

On Tuesday, the appeals court is scheduled to hear those argument in Muhammad's bid to overturn his conviction and death sentence or return the case to the trial court for whatever further proceedings the appellate judges might deem appropriate.

Muhammad made his own opening statement and cross-examined witnesses for the first two days of his 2003 trial before turning the case back over to his court-appointed attorneys. His new lawyers claim on appeal that the failure to prevent him from representing himself violated his constitutional right to an effective defense.

A jury in Virginia Beach sentenced Muhammad to death for the Oct. 9, 2002, murder of Dean Meyers in Prince William County. In all, the shooting spree by Muhammad and Lee Boyd Malvo left 10 dead and a half-dozen wounded in four states and the District of Columbia.

Along with the ineffective defense claim, a three-judge panel of the appeals court will consider two other issues raised by Muhammad: that the prosecution withheld crucial evidence and that the trial judge erred in refusing to allow the jury to hear expert testimony about Muhammad's brutal childhood.

Muhammad's lawyers describe him in court papers as "an inarticulate high school graduate with no college experience or knowledge of the law." They say an MRI of his brain showed abnormalities and two experts said he likely was schizophrenic.

But the attorney general's office says in its brief that Muhammad was lucid and coherent in answering the trial judge's questions, and his own attorneys "found him very bright and knowledgeable about the case based on many months of interaction."

Muhammad also claims prosecutors withheld thousands of pages of documents that could have helped his defense, including an FBI profile developed before the arrests suggesting a lone sniper was responsible. According to Muhammad, that document contradicted an expert's testimony that snipers operate in teams — a shooter and a spotter.

State attorneys say the profile was just "law-enforcement's best guess about the type of at-large murderer who was randomly killing citizens along I-95," and noted that Muhammad's attorneys omitted this key sentence from the report: "If there is a second offender, he is not likely to be an equal partner in these crimes, and would be subservient to the primary offender."

Prosecutors argued in Muhammad's trial that he directed the killings and therefore was as culpable as the obedient Malvo, who carried out the shootings with a high-powered rifle from the trunk of a Chevrolet Caprice that had been converted into a sniper's nest.

However, Muhammad claims the prosecution also withheld a dozen letters Malvo had written to another jail inmate that could have been used to undermine the state's theory "that Malvo was a meek, malleable young man who only did what he was told by Muhammad."

Prosecutors in Malvo's trial used the letters to counter his claim that he had been brainwashed by Muhammad. Malvo is serving a life term for his role in the killings.

Attorneys for the state point to previous court rulings that the letters were unlikely to change the outcome of Muhammad's trial.

The state also says the trial court's refusal to let a psychologist testify at trial's penalty phase about Muhammad's rough upbringing was proper because Muhammad had refused to cooperate with the prosecution's mental health expert.