CHESAPEAKE, Va. - A psychologist for the defense told jurors yesterday that sniper suspect Lee Boyd Malvo was so thoroughly brainwashed by John Allen Muhammad's regimen of hatred that he agreed to "martyr" himself in the event the two were captured.

Dewey G. Cornell testified that Malvo's indoctrination was so complete that the teen-ager falsely confessed to police in November last year, hoping to protect Muhammad.

Although Malvo told police that he pulled the trigger in nearly all the killings, Cornell heard a different story: Malvo said he was only the spotter, not the triggerman, in all but the last sniper shooting.

The indoctrination included firearms training, screening of violent movies, playing sniperlike video games and trips to the slums of the large cities on the East Coast to see how poor people were living, Cornell said.

"He was being psychologically indoctrinated and subjected to coercive persuasion by John Muhammad," said Cornell, a University of Virginia professor and court-appointed expert who studies troubled juveniles. "He was isolated from family friends and familiar surroundings. He was undergoing strict control of his daily activities. [Muhammad] exposed him to repeated violence through movies, military training and video games."

Muhammad, who was convicted last month in the attacks that terrorized the suburbs around the nation's capital, fired the shots and controlled the killing scenarios, Malvo told Cornell. That includes the killing of FBI analyst Linda Franklin for which Malvo is on trial.

The psychologist spent all day on the witness stand, the 17th day of Malvo's capital murder trial.

"Mr. Muhammad said if I ever back down you should shoot me and not abort the mission," Cornell said. "Lee understood that to mean that if he backed down, Mr. Muhammad would shoot him. He understood that if he was to be arrested he was to self -destruct. ... There was no turning back in this mission."

Cornell's testimony is considered crucial to the defense, which is contending in an insanity plea that Malvo could no longer tell right from wrong. If the jury finds he was insane at the time of the Washington-area sniper siege, Malvo will be committed to a Virginia mental institution.

If the jury convicts Malvo of capital murder in the Oct. 14, 2002, death of Franklin, it will then choose between a sentence of execution or life without parole in prison. Franklin, shot in the head in the parking lot of a Home Depot near Falls Church, Va., was one 10 people killed in the Washington area during the snipers' three-week rampage.

A particular influence on Malvo was the film The Matrix, Cornell said. Malvo watched the movie hundreds of times, including just before the shooting of Franklin.

Over objections by Fairfax County Commonwealth's Attorney Robert F. Horan Jr., Fairfax County Circuit Judge Jane Marum Roush let jurors watch an especially violent clip from The Matrix yesterday, in which the characters Neo and Trinity machine-gun their way past guards. The jurors also saw excerpts from five video games that Malvo said he was trained on, including the "god mode" of Ghost Recon, in which the shooter is invincible.

But Horan contended that millions of people have seen The Matrix and played violent videos without growing up to become killers. Cornell said Malvo was especially taken with the world view of The Matrix and saw himself as Neo, the film's hero, who shoots his way out of an oppressive world. Malvo saw that as his mission.

"He told me that right and wrong did not exist, that was something he had to keep out of his mind because that was constructed by an oppressive government," Cornell said. "Right and wrong was an illusion, and the only thing that mattered was that he do what was required of him."

But Horan contended that Malvo was predisposed to violent acts. Malvo took an intense dislike to cats and killed them as a boy because his pet cat often soiled his bed, an action that caused Malvo's mother to beat him, Cornell said.

Using a slingshot, Malvo took to blasting marbles at stray cats in his native Jamaica. He didn't know how many he killed, Cornell said. Despite hammering from Horan, Cornell did not say that killing animals forecasts violence against people, but he did allow that some studies indicate that adult killers killed animals in their youths, and "it is an indication of emotional problems." He said Malvo also told him that he shoplifted comic books and other items.

Cornell testified that Muhammad fed Malvo his own bizarre philosophical blend, telling Malvo that "he felt they had been selected by Allah to free the oppressed black people of this country" and that the Sept. 11, 2001, terrorist attacks were "evidence that the revolution was coming."

To train Malvo, Muhammad filled the teen-ager's head with tenets of anti-white racial hatred, anti-Americanism, his version of Islam and the need to fulfill a "mission" to set the world on what Muhammad identified as the correct path. He desensitized him to killings, Cornell said, by having him play sniper video games.

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