Dr. Gilles Chamberland said Thursday that Magnotta, over a 48-hour span in May 2012, dismembered and disposed of Lin's body, emptied his apartment and prepared for a trip to Europe.
The psychiatrist said one symptom of schizophrenia is disorganization, but he described Magnotta's actions as "ultra-organized." Chamberland noted the accused even found time to set up an online escorting profile and meet a client after arriving in Paris.
"That's a lot in 48 hours and to do all that, you've got to be very organized," he said. "The gentleman appeared able to do all of it."
Magnotta, 32, is charged with first-degree murder in Lin's slaying. The native of Scarborough, Ont., has pleaded not guilty by way of mental disorder.
Defence psychiatrists have testified they believe Magnotta was psychotic, had been untreated for schizophrenia for at least two years and was unable to tell right from wrong the night Lin was killed.
The Crown has countered the crime was planned and deliberate and Chamberland, a rebuttal witness, said he believes the accused was sane and aware of his actions.
Chamberland also believes Magnotta may not have schizophrenia and that he suffers from a personality disorder that better explains his actions. His findings are not definitive as they are based on the reports of others and because Magnotta declined to meet with him.
The Crown's expert is of the opinion that Magnotta's previous schizophrenia diagnosis is probably erroneous and that seemingly psychotic episodes in the past were linked to drug use. He said the schizophrenia diagnosis appeared quickly in medical files in 2001.
Chamberland noted that a German prison psychiatrist who diagnosed Magnotta in June 2012 as being psychotic did so based on Magnotta's own ramblings that centred specifically on family history, general paranoia and symptoms such as hearing voices.
The answers Magnotta gave Dr. Thomas Barth focused on his illness and painted himself as a victim, Chamberland said. The accused also downplayed drug and alcohol consumption. Barth described his answers as confusing and scattered.
Chamberland views things differently and contends Magnotta was offering up the exact ingredients to ensure schizophrenia would be the only diagnosis.
"For me, this is anything but disorganized thinking," he said, adding it would be difficult for a treating psychiatrist to come up with another conclusion.
"With that (information), and only that, any doctor will retain a schizophrenia diagnosis," Chamberland said.
He believes the accused's behaviour is better explained by a histrionic personality disorder, whereby patients are dramatic and exhibit attention-seeking behaviour.
"For me, in this case, I don't see a lot of evidence of schizophrenia," Chamberland said. "Magnotta's actions appear to be more influenced by his personality and simulation than by schizophrenia."
Almost all the psychiatrists who saw Magnotta diagnosed him with some personality disorder traits, Chamberland noted.
Magnotta faces four other charges: criminally harassing Prime Minister Stephen Harper and other members of Parliament; mailing obscene and indecent material; committing an indignity to a body; and publishing obscene materials.
Quebec Superior Court Justice Guy Cournoyer said evidence is expected to wrap up early next week and he told jurors they wouldn't be deliberating until the end of the week beginning Dec. 8.
The trial is adjourned until Monday when it begins its 10th week.
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