John Lee Cowell was convicted Tuesday of first-degree murder and other charges for the fatal stabbing of 18-year-old Nia Wilson at the MacArthur BART station in Oakland in 2018.
Jurors only deliberated for about two hours before announcing their verdict against Cowell, a 29-year-old transient man with a history of mental illness, for the stabbing at the MacArthur station at about 9:35 p.m. on July 22, 2018.
Jurors also convicted Cowell 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.
Cowell, who pleaded not guilty by reason of insanity, could face life in prison without the possibility of parole.
However, on Wednesday a separate sanity phase will begin in which the same jury will decide if he was legally sane at the time of the attack.
If Cowell is found to have been insane at the time of the attack he would serve his sentence in a state mental hospital instead of prison.
Cowell was absent from most of his trial, either because of outbursts or because he's refused to come to court.
But he was in court on Tuesday morning when Alameda County prosecutor Butch Ford presented his rebuttal closing argument and was present again on Tuesday afternoon when the jury announced its verdict.
Dressed in a blue-and-white checkered shirt, Cowell looked straight ahead and didn't react when the verdict was read.
However, many of Wilson's family members sobbed when the verdict was announced.
Ford and defense attorney Christina Moore declined to comment after the verdict because Cowell's trial isn't yet over.
Wilson's family members also declined to comment.
In his rebuttal argument, Ford said Cowell should be convicted of first-degree murder and the other charges against him because he knew what he was doing.
Ford said, "I'm not disputing that he has some sort of mental health issue but I'm disputing that it played a role in the stabbing."
Moore admitted in her closing argument on Monday that Cowell stabbed Nia and Letifah Wilson but said he's been diagnosed with paranoid schizophrenia and his mind "was completely divorced from reality" at the time.
However, Ford told jurors on Tuesday that Cowell admitted on the witness stand that he intended to stab the two sisters.
Ford said, "He tells you and the video (of the stabbing) shows you he meant to do it."
Nia Wilson, Letifah Wilson and a third sister boarded a San Francisco-bound train at the Concord BART station the night of July 22, 2018, after attending a family gathering for someone who had been killed. Cowell got on the same train at the Concord station.
Ford alleged that Cowell didn't attack the Wilson sisters on the train because he wouldn't have had a chance to flee quickly but instead waited to attack them when they changed trains at the MacArthur station.
Ford said, "He attacks them when they're most vulnerable. He knew what he was doing."
