Marie-Frederique Allard told Magnotta's first-degree murder trial on Monday it would have been difficult for the accused to simulate such symptoms over an extended period of time.
The Crown has suggested that Magnotta, 32, was putting on an act while detained at a German prison hospital following his arrest in Berlin in June 2012.
Allard, a defence witness, disputed that assertion, calling Magnotta a classic schizophrenic. She first met with Magnotta in December 2013 — 19 months after the homicide.
The forensic psychiatrist said Magnotta's rambling responses in Germany are similar to previous symptoms noted in his voluminous medical history: paranoia, hearing voices, and the fear of being attacked.
Allard said Magnotta also spoke during that German stay about elements linked to charges: notably the mention of the Canadian government and branding Prime Minister Stephen Harper as evil.
"For me it's clear, I think the medical files clearly show that Mr. Magnotta suffers from schizophrenia," said Allard. "We have an evolution that's pretty classic or typical of a young man who suffers from schizophrenia."
Allard previously testified she believes Magnotta was suffering from schizophrenia and in a psychotic state when he killed Lin in May 2012.
Allard's opinion is that Magnotta knew what he was doing but the psychosis meant he wasn't able to differentiate right from wrong.
Magnotta has admitted to killing the 33-year-old Chinese engineering student but pleaded not guilty by way of mental disorder.
The Crown contends Magnotta's actions were planned and deliberate in Lin's homicide.
He faces four other charges: criminally harassing Harper and other members of Parliament; mailing obscene and indecent material; committing an indignity to a body; and publishing obscene materials.
The medical records dating back to 2001 provide some of the answers: they suggest numerous highs and lows with Magnotta's treatment for schizophrenia.
Those records suggest Magnotta was often concerned about others spying on him, had auditory hallucinations and wasn't vigilant about taking medication to treat his schizophrenia.
Magnotta was under psychiatric care while living in Ontario. Allard mentioned a Dr. Thuraisamy Sooriabalan, who saw him between 2002 and 2008.
Sooriabalan noted Magnotta's family history of schizophrenia — his father suffers from the same illness.
Magnotta never exhibited violence and apparently was not addicted to drugs or alcohol, Sooriabalan said in one report mentioned by Allard.
Various reports from Sooriabalan highlight some bizarre moments: Magnotta told the doctor at one point about having joined Scientology. Later, in August 2007, Magnotta complained he was the subject of published rumours linking him to schoolgirl killer Karla Homolka. He also lashed out at his father and often expressed concerns he was being followed or watched by unknown people.
After being diagnosed with schizophrenia, Magnotta was hospitalized several times and lived in a group home for patients with the mental disease.
The medical files indicate Magnotta stopped seeing a psychiatrist as of July 2010.
There were two hospital visits noted after that — one in Miami in 2011 and one at the Jewish General Hospital in Montreal in April 2012 — one month before Lin's slaying.
Magnotta either denied having mental health problems or did not make mention of being diagnosed as schizophrenic during either visit.
During the Montreal visit, Magnotta told doctors he was bipolar, withholding his previous schizophrenia diagnosis. No medication was prescribed that day.
Allard said there wasn't enough information for doctors to make a proper diagnosis. Magnotta told Allard much later why he kept mum.
"He was fearful of being hospitalized if he put his symptoms forward," Allard said.
Her testimony continues Tuesday.
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