OAKLAND, Calif. (KRON) – An Alameda County jury deliberated for less than three hours before reaching a verdict in the Nia Wilson murder trial Tuesday afternoon.

John Lee Cowell was found guilty of all charges: first-degree murder, attempted murder, and lying in wait. Deliberations are not over, however, because Cowell pleaded not guilty by reason of insanity.

Starting Wednesday afternoon, the same jury will decide whether he was sane or insane when he attacked Wilson and her sister on a BART train July 22, 2018. Wilson, 18, died minutes after Cowell slashed her throat. Her sister, Letifah Wilson, was also stabbed in the neck and survived.

Nia Wilson
Nia Wilson / Facebook

Cowell told family members and jail staff workers that he’s “hopeful” the jury will find him not guilty by reason of insanity, also known as NGI, so that he could be released someday and live with his family again. If Cowell is NGI, he will be sent to state psychiatric hospital. If the jury’s verdict strikes down the NGI plea, he would be sent to prison and likely sentenced to spend the rest of his life behind bars.

MORE: Defense attorney tells Nia Wilson’s supporters: ‘This trial is not about you’

While Cowell refused to attend most of the trial, he did appear in court Tuesday just before deliberations began. As judge Allan Hymer was reading instructions to the jury and mentioned the words “acquittal” and “not guilty,” Cowell made strange celebratory fist pumps and head nods. Cowell was urged by his defense attorney to “stop it,” and to listen quietly.

MORE: Who is the real John Cowell?

Ford said Cowell is trying to “put on a show” by acting strange in court, going off his anti-psychotic medication, faking a stoic, robotic persona on the witness stand in an effort to gain enough sympathy from jurors that they find him not guilty by reason of insanity.

“He wants to look crazy. He’s trying to fool all of you,” Ford told the jury Tuesday morning.

Ford pointed out moments when witnesses who interacted with Cowell after the homicide said he appeared to be normal, and not suffering from delusions or hallucinations. Immediately after killing Nia Wilson, Cowell blended into the crowd by running, changed the clothes he was wearing, hid the knife in a construction yard, and caught a city bus. Ford said Cowell’s behavior was “goal-oriented, organized, methodical, adaptable, and planned.”

“This is first-degree murder. His goal is to avoid responsibility. Justice demands you find him guilty,” Ford said.

The homicide was recorded by BART’s surveillance cameras and the gruesome video was shown repeatedly during the trial. An eerie 26-minute BART ride happened between the Concord and MacArthur stations, in which Cowell and Nia Wilson rode on the same train a few feet away from each other. They never spoke or interacted before he followed her off the train and attacked as she was stepping into a different train.

Nia Wilson
Artwork of Nia Wilson and a BART map

To the surprise of some trial observers, Cowell testified in his own defense. He said he attacked the “black females” because they were “aliens” and “gang members” who kidnapped his grandmother. Cowell admitted he’s the man with the knife in the surveillance footage. Cowell asserted that he did nothing wrong because he was trying to save his grandmother from the alien kidnappers.

Ford asserted that, if Cowell really believed that he was doing the right thing by attacking his grandmother’s “kidnappers,” why would he immediately run, get rid of the murder weapon, and hide by changing his appearance?

Cowell was removed from the courtroom in the middle of his testimony when he became increasingly irate and swore at lead prosecutor Butch Ford for being “disrespectful.”

MORE: Aliens & fake skin: John Cowell testifies, describes why he stabbed Nia Wilson

Public defender Christina Moore built her defense case around trying to convince the jury that Cowell is legally insane, that his violent act was spontaneous, and that he driven by delusions with complete disconnect with reality. “John Cowell acted because of his delusional misinterpretation of the world. John was actively psychotic with hallucinations and disillusions,” she said.

MORE: “Evil” debated in opening statements

John Lee Cowell Mugshot
John Lee Cowell

Moore said the trial centers on one question: “What was in his mind on July 22, 2018?”

Ford also built his case around what was in Cowell’s mind.

“Evil exists in this world and cause terrible things to happen to innocent people. All of those things came together at the MacArthur BART station. Evil in this case has a name, and its name is John Lee Cowell,” Ford said.

Ford focused on trying to prove that Cowell lies, manipulates, exaggerates his mental illnesses and made his delusions worse by abusing heroin and methamphetamine.

The witnesses called by Moore to testify were mostly psychiatrists who treated Cowell
during dozens of hospital stints. He told doctors that he was hearing voices, feeling paranoid, and wanted prescription drugs.

MORE: What happens to murder defendants who are found not guilty by reason of insanity?

He was diagnosed with schizophrenia, personality disorder, bipolar disorder, as well as disorders caused by long-term, chronic street drugs abuse. A key witness was Cowell’s aunt, Saundra Ferriera, because she witnessed Cowell’s mental decline progress over a decade, starting around his 18th birthday. Cowell called her just a few hours before the homicide saying he was feeling very paranoid, but she didn’t hear the voicemails until Cowell had already stabbed the Wilson sisters.

MORE: Nia Wilson murder trial nears an end as unpredictable events continue

The aunt explained that Cowell’s closest relationship was with his grandmother because, since he was 4 years old, his mother was institutionalized in a mental hospital. As time passed, Cowell became more and more like his mentally ill mother, Ferriera testified. Cowell was never able to attend his grandmother’s funeral because he was incarcerated in prison at the time. Cowell developed a belief that his grandmother was still alive, but was somewhere being tortured by alien kidnappers, his aunt testified.

Moore told the jury that, even if they believe that Cowell’s guilt is “highly likely,” they still have to return with a not guilty verdict, and reminded them that the burden of proof is on the prosecution.

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