"Lee was unable to distinguish between right and wrong and was unable to resist the impulse" to commit the killings, said Neil Blumberg, who examined Malvo 20 times in jail. "From day one, I thought he met the legal criteria for insanity."
Psychiatrist Diane Schetky, who twice interviewed Malvo, also testified that Malvo was unable to tell right from wrong - the legal standard for insanity in Virginia.
Defense mental health experts have said Malvo, 18, was taught by Muhammad that right and wrong are artificial concepts and that the winner in a war determines who is right and who is wrong. Muhammad likened the sniper attacks to a war against the United States government, which he said oppresses blacks.
In his initial report, Blumberg said Malvo, who was 17 at the time of the shootings, was "severely impaired" in his ability to tell right from wrong. Prosecutor Robert F. Horan Jr. accused Blumberg of changing his opinion to suit the defense.
Blumberg said he had been trying to follow what he had thought were the requirements of Virginia law, which does not ask mental health experts to render an opinion on whether a patient meets the legal definition of insanity.
Schetky said on cross-examination that she believes Malvo knew right from wrong during a slaying eight months before the sniper spree, which left 10 dead in and around Washington, D.C., in October 2002. Malvo has confessed to killing Keenya Cook in Tacoma, Wash., on Feb. 16, 2002.
Schetky said she believes Malvo was aware killing Cook was wrong, although Blumberg disagreed. Malvo believed Muhammad would reject him if he did not kill Cook, Schetky said.
Malvo's attorneys are presenting an insanity defense to capital murder charges in the death of FBI analyst Linda Franklin, who was shot on Oct. 14, 2002, outside a Home Depot.
Schetky diagnosed Malvo with a dissociative disorder, a mental illness that she said distorted Malvo's perception of reality, a result of indoctrination by Muhammad.
Blumberg said Malvo still has the disorder, citing as evidence the defendant's constant doodling during a trial in which he could be sentenced to die.
Schetky testified that Malvo "displayed a pathological loyalty to Muhammad" during his confession in which he took responsibility for being the triggerman in all the D.C.-area shootings.
Malvo has since told psychiatrists that Muhammad was the triggerman in nearly all the shootings. A jury convicted Muhammad last month and recommended he be put to death.
Schetky said Malvo felt conflicted about the Oct. 7, 2002, shooting of 13-year-old Iran Brown outside a Bowie, Md., middle school. He thought killing children "was very wrong ... but he was complying with the plan." She said he was "relieved the shot did not kill him."
Horan has suggested the conflicted feelings prove Malvo knew right from wrong.
By Adrienne Schwisow