Murder defendant in Nia Wilson case removed after profanity-laced tirade, victim's family calls it an act

OAKLAND, Calif. (KGO) -- The sister of BART stabbing victim Nia Wilson doesn't buy that Nia's alleged killer testifying in his own defense is mentally ill.

"It's just an act to me. What I've seen? Manipulation," said Letifah Wilson, who was also injured the night of July 22, 2018 at the MacArthur BART station, but survived her stab wounds. "He wants to project his feelings on to others, so we won't get an answer."

John Lee Cowell lasted just 15 minutes on the witness stand. During cross examination by Alameda County prosecutor Butch Ford, Cowell became combative, saying he recognized the knife held up before him but not the July 2018 stabbing, even as he identified himself in a surveillance video.

RELATED: John Lee Cowell gives bizarre testimony in trial for murder of Nia Wilson at BART station

"I don't remember anything like that. What is this that we're watching?" said Cowell, pointing to a large video screen next to him.

As the prosecutor tried to show a slow-motion video, Cowell kept interrupting, finally yelling "Back the f*%# down." When he was ordered to leave the witness stand, "Now they can't force me to say sh** if I'm f*#*ing leaving."

Cowell was escorted out of the coutroom by two deputies and was not present when his aunt testified that he had exhibited paranoia and symptoms of mental illness since childhood, claiming to see aliens and "fake skins."

RELATED: Man accused of killing BART rider Nia Wilson thrown out of court during trial opening statements

Jocelyn Gama says she was a close friend of Nia Wilson.

"She was a beautiful soul. She was a brilliant girl and there's more to her story than just this," said Gama.

His defense team has tried to paint the 29-year-old Cowell as mentally ill, while prosecutors say he was a drug addict, whose attack on Wilson and her sisters was racially motivated.

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