Judge suspends criminal proceedings for Nia Wilson's alleged killer

OAKLAND, Calif. (KGO) -- The criminal case against the man accused of murdering Nia Wilson at MacArthur BART last summer has been suspended while psychiatrists determine if he is competent to stand trial.

A judge Thursday ordered the mental examination for 27-year-old John Lee Cowell.

RELATED: Father of BART stabbing victim Nia Wilson questions alleged killer's mental health delay

Outside the courtroom today, Nia Wilson's father was clearly disappointed that the criminal case was put on hold pending the psychiatric examination. The defense attorney for Cowell says he's showing signs of delusion and paranoia. Wilson's father disagrees.

"If this guy could do what he did and change his clothes and carry out what he did so smoothly, you know, I think that's pretty competent," said Ansar Mohammed, Nia Wilson's father. "I want justice for my daughters. That's the only thing I want is justice for my daughters... fair justice for my daughters."

After that statement a reporter asked if justice to him would be the death penalty.

"Nah, I leave that to the creator, that's not my decision," replied Mohammed.

Police allege that Cowell attacked the sisters on the MacArthur Bart platform then wiped off the knife, dumped it in a nearby construction yard and changed his clothes.

RELATED: Death penalty decision delayed in Nia Wilson BART stabbing case

UC Hastings law professor David Levine says Cowell's attorney could be laying the groundwork for an insanity defense. But proving that is difficult.

Levine says, "You either have to show that you didn't understand what you were doing -- you thought you were catching butterflies, not that you were slashing somebody with a knife. Or that you didn't know it was morally wrong."

There may be a time out in the criminal case, but the Wilson family's civil case against BART for allegedly failing to keep dangerous people out of the stations and off the trains is not affected.

The family's attorney Robert Arns said, "We're not talking so much about the culpability of the perpetrator. We're talking about the laxity of BART."

The judge has scheduled the hearing on Cowell's psychiatric report for February. But the victim's family is still pushing for a death penalty trial.

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