OAKLAND, Calif. (KRON) — It took just two hours for an Alameda County jury to find John Cowell guilty of murdering 18-year-old Nia Wilson, and attempting to murder her sister, Letifah Wilson, on a BART train in the summer of 2018. Wilson’s family, friends, and supporters cried with relief and rejoiced outside the courthouse.

But they also knew a second verdict was still to come, one that would determine if Cowell could one day walk free. That is because Cowell pleaded not guilty by reason of insanity.

Jury deliberations for the sanity phase began Wednesday afternoon and, as of Thursday afternoon, deliberations were still underway.

Cowell suffers from mental illness, including schizophrenia, prosecutor Butch Ford and defense attorney Christina Moore said throughout the trial.

For the jury to find Cowell not guilty by reason of insanity, the defense had to prove that, at the time of the murder,

  1. Cowell was suffering from a mental disease.
  2. Cowell’s mental disease prevented him from being able to understand his actions.

The judge gave deliberation instructions to the jury Wednesday and said they were not allowed to consider: what will happen to Cowell if their verdict declares him as insane or sane at the time he attacked two young women whom he had never met?

This verdict will decide if Cowell is sent to a state mental hospital or a state prison. California’s mental hospital system and prison system are very different from each other, legal experts told KRON4.

MORE: Not guilty by reason of insanity: what would happen next?