Graham Veitch has not been found criminally liable in the 2016 killing of David Collins, his mother's partner.
Justice Sandra Chaytor settled the ruling Thursday morning in a St. John's Court Room, which called the situation a "tragedy".
Veitch was accused of second-degree murder and admitted that he killed Collins.
Chaytor said she believes Veitch lacked the ability to know that his actions were wrong because it does not mean he is free to go.
Veitch has been placed under supervision at Waterford Hospital with the goal of being rehabilitated and now having contact with her mother.
Tears in court as Judge Chaytor reads details of what happened in December 2016 when David Collins died.
Both the Crown and the Defense agreed that Veitch, 21, who was diagnosed with schizophrenia, was undiagnosed and in a state of psychosis when he killed Collins.
Both parties argued that Veitch would not be held criminally liable because of his mental state.
"This is really a very tragic case," Chaytor said when arguments ended in June.
Veitch has been detained in Her Majesty Penitentiary for most of the last 30 months.
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