As a child, Malvo killed stray cats with a slingshot beginning at age 8 or 9 and continued the anti-social behavior for nearly five years, Neil Blumberg testified at Malvo's capital murder trial.
Malvo also regularly stole comic books and compact discs, said Blumberg, who spent 50 hours with the teenager over 20 interviews.
"All of that behavior would have been before he ever met John Muhammad, correct?" prosecutor Robert F. Horan Jr. asked Blumberg. The psychiatrist agreed.
Also Thursday, the judge dismissed a 22-year-old juror because the man lives outside Chesapeake. City spokesman Mark Cox said the judge "acknowledged that this was an innocent mistake on the part of the juror. It will not impact the outcome of the trial." The jury now has 15 members, including three alternates.
Malvo's lawyers claim Malvo, 18, is innocent by reason of insanity and was brainwashed by Muhammad, who was convicted last month of masterminding the sniper spree that killed 10 people in the Washington, D.C., area. Malvo is on trial for one of the killings; another jury recommended the death penalty for Muhammad, who was convicted in another of the killings.
On Wednesday, Blumberg testified that Malvo's mental diseases left him "psychologically numb" and legally insane because he couldn't tell right from wrong.
Blumberg's statements under cross-examination echo earlier testimony from a defense psychologist who said Malvo killed cats as a child. Blumberg said Malvo had grown to hate cats because his mother frequently beat him after Malvo's pet cat would soil his sheets.
The psychiatrist said shoplifting and cat-killing were signs of a childhood conduct disorder that combined with later mental illness to make Malvo "unable to distinguish between right and wrong" and "unable to resist the impulse" to commit the sniper killings in 2002.
Malvo also suffered from depression and a dissociative disorder that allowed him to tune out reality, lose his sense of identity and become vulnerable to Muhammad's wishes and "intense, coercive persuasion," Blumberg testified.
Psychiatrist Diane Schetky, who twice interviewed Malvo, also testified that she believed Malvo was unable to tell right from wrong.
The standard for legal insanity in Virginia is an inability to distinguish right from wrong at the time of the crime. Defense mental health witnesses have testified that Muhammad taught Malvo that right and wrong are artificial concepts created by the government.
Malvo's attorneys argue he latched on to Muhammad three years ago because his childhood of loneliness and uprooting left him malleable and without a father figure. Malvo told the psychiatrists that he and Muhammad planned to wage a war for racial justice against America.
The prosecution was expected to call its own mental health experts to the stand.
Earlier witnesses, including former teachers and schoolmates of Malvo, testified that as a child Malvo was a good student, respectful and generous. Some testified that he seemed to follow Muhammad's example in many ways, including adopting a strict diet and workout regimen, learning to shoot a gun and converting to Islam.
Prosecutors began the trial by playing back interrogation interviews tapes of Malvo, then 17, bragging about his shooting skill and telling authorities he pulled the trigger in all the sniper attacks.
By Adrienne Schwisow