SASKATOON -- During the cross-examination of a key defence witness, the Crown questioned the legitimacy of the accused’s diagnosis.

Forensic psychiatrist Dr. Mansfield Mela testified he diagnosed Blake Schreiner with a disorder on the schizophrenia spectrum.

Crown prosecutor Mel Kujawa grilled Mela about the diagnosis at Court of Queen’s Bench on Tuesday.

Schreiner is charged with first-degree murder in the death of his partner, Tammy Brown.

The 39-year-old woman was found with more than 80 stab wounds on Jan. 29, 2019. The couple’s two children were home during the stabbing.

The Crown is arguing Schreiner planned Brown’s murder, while the defence is trying to establish Schreiner’s mental state rendered him incapable to appreciate his actions.

Mela told court that Schreiner’s judgement was impaired during the stabbing and “he did not know what he was doing was wrong,” referencing the accused’s schizotypal personality disorder diagnosis.

During the cross-examination, Kujawa pointed to inconsistencies between Mela’s report and other psychiatrists’ findings.

Mela agreed the psychologist at Saskatchewan Hospital North Battleford didn’t diagnose Schreiner with schizotypal personality disorder. Mela also agreed Schreiner’s past medical records didn’t mention hallucinations or paranoia.

Earlier in the trial, Schreiner testified he heard voices in his head leading to Brown’s death and was paranoid he was going to be killed.

But in a police confessional video, Schreiner didn’t mention to officers he heard voices or believed Brown was trying to kill him.

Schreiner also didn’t tell doctors at Sask. Hospital about the voices or his paranoia, court heard.

Kujawa raised questions about why Mela didn’t reach out to family members, or friends, for confirmation about Schreiner’s behaviour — which lead to Mela’s diagnosis.

“You just took the accused’s word for everything, didn’t you?” Kujawa asked.

“I took his words and my observations,” Mela responded.

“Did you do anything to confirm your observations with how other people viewed with Mr. Schreiner? Did you talk to any family members or friends?” Kujawa asked.

“No I didn’t,” the psychiatrist answered.

In Schreiner’s journal, he wrote he was under the influence of psilocybin, known as magic mushrooms, while stabbing Brown.

But in a second journal, Schreiner changed his account to reflect he was actually sober.

Mela said even if Schreiner was on mushrooms during the stabbing, most people realize their hallucinations aren’t legitimate and Schreiner had “crossed over to the psychotic path.”

During the proceedings, Schreiner sat upright beside two sheriffs. He wore a suit behind glass in the prisoner’s box that was recently installed as a COVID-19 precaution.

The trial is scheduled to continue all week.