OAKLAND (CBS SF) — The judge in the trial of John Lee Cowell for the fatal stabbing of 18-year-old Nia Wilson at an Oakland BART station in Oakland in 2018 ruled on Monday that he was legally sane at the time.

Jurors in Cowell’s trial only deliberated for one full day about whether Cowell, a 29-year-old transient man, was sane at the time he fatally stabbed Wilson at the MacArthur station in Oakland at about 9:35 p.m. on July 22, 2018.

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But Alameda County Superior Court Judge Allan Hymer decided to issue a directed verdict in the matter on Monday because four of the jurors in Cowell’s case are older than 65 and Gov. Gavin Newsom has asked people 65 and older and those with chronic health conditions to stay indoors in response to the novel coronavirus pandemic.

Cowell’s attorney Christina Moore objected to the directed verdict and asked that jurors be allowed to continue deliberating.

In the guilt phase of the trial, the same jury convicted Cowell of first-degree murder for the fatal stabbing of Nia Wilson and of premeditated attempted murder for stabbing Wilson’s sister Letifah Wilson, who was injured but survived the attack.

In addition, jurors found true a special circumstance allegation that Cowell murdered Nia Wilson by lying in wait for concealing his intent and then killing her by taking her by surprise.

Tensions ran high throughout the emotionally charged trial. On the first day, Cowell was removed from the courtroom following an outburst during the prosecution’s opening remarks. The judge first admonished Cowell for speaking out to defend himself, telling Cowell to keep quiet and ultimately having Cowell removed when he continued.

When Cowell took the witness stand, he told jurors he hears voices from alien technology implanted in his ear in a series of bizarre ramblings.

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Cowell sparred with his attorney during her questioning, testifying that he heard voices in his head that came from alien technology implanted in his ear with aliens using a radio to communicate with him.

He also referred to people wearing “fake skin” and “skin suits,” insisting that the Wilson sisters were aliens that were threatening him. Cowell also said the sisters had kidnapped his grandmother and were threatening to hurt her.

Cowell said that the sisters were standing over him on the BART train and staring him down and that attacking them was the only way to save his grandmother.

A short sanity phase was held Wednesday afternoon and jurors deliberated for about an hour late Wednesday and a full day on Thursday but didn’t meet on Friday.

Cowell, who pleaded not guilty by reason of insanity, now faces life in prison without the possibility of parole.

If jurors had ruled that he was insane at the time of the attack, he would have served his sentence in a state mental hospital instead of prison.

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Hymer is scheduled to sentence Cowell at a hearing on April 4 if the courts are open then.