A Toronto senior has been found guilty of second-degree murder in the death of a fellow long-term care home resident.

Peter Brooks, 76, had pleaded not guilty to first-degree murder in the death of 72-year-old Jocelyn Dickson.

He was also charged with attempted murder of 91-year-old Lourdes Missier but was found not guilty on that charge.

The trial heard Brooks, who came to Canada from Jamaica decades ago, had testy relations with both women who were attacked, who he described as "annoying" and aggravating him constantly.

Brooks believed fellow residents 'conspiring against him': lawyer

The jury heard Brooks allegedly attacked Missier first, swinging his cane at the head of the woman who was awake at the time and raised her hands to protect herself. She was left with fractured fingers, bruises and lacerations on her face.

While staff were responding to what happened to Missier, Brooks quietly made his way to another floor, where Dickson, a woman who was paralysed on one side of her body, was asleep in her bed, the trial heard.

Police were called to this seniors home late one night in March of 2013. (Tony Smyth/CBC)

Using his cane once more, Brooks delivered at least seven distinct blows to Dickson's head causing "massive" injuries that led to the woman's death, the Crown has said. The force of the blows was strong enough to break off the top of Brooks' cane.

The trial heard that Brooks then tried to make his way to the room of another woman he had a rocky relationship with but was stopped by staff who, only after a violent struggle, were able to wrestle away his cane.

Brooks' lawyer had argued that his client believed residents at the Wexford were "conspiring against him" and consequently felt justified in his actions because of his delusional belief.

Defence argued staff mishandled events on night of attack

The defence lawyer also suggested staff at the nursing home completely mishandled the situation on the night of the attacks, calling them "incompetent and ill-equipped."

Brooks took the stand in his own defence and testified he believed the women he attacked were united in an alleged attempt to have him moved out of the facility.

Brooks testified that a spirit in a dream told him to "beat the crap" out of his two fellow residents, and insisted he didn't actually intend to harm anyone.

Toronto police taped off a door in The Wexford after the alleged murder and attempted murder. (Supplied)

Two forensic psychiatrists who testified at the trial found Brooks had dementia, though they disagreed on the level of the condition, with one saying it was mild and the other saying it was moderate.

Both psychiatrists also agreed Brooks has damage to the frontal lobe of his brain — which deals with impulse control, emotional regulation and perspective — appeared disinhibited, and did not appear to appreciate the seriousness of the proceedings against him.

Psychologists disagreed on effect of dementia

The psychiatrists disagreed, however, on the extent of the dementia's effect on Brooks and his actions -- one found it was only probable that Brooks was acting on a delusion on the night of the attacks while the other said it was possible.

The trial also heard from a geriatric psychiatrist who assessed Brooks a year before the attacks and found the senior represented a "chronic risk" to the home's frail residents.

Dr. Stephen Barsky told the trial that he examined Brooks in April 2012 after receiving reports of three incidents of aggression by the man against other residents at the home and found the man somewhat irritable, sarcastic and not fully co-operative.

Barsky said he had concerns about Brooks' level of judgement and felt the senior would be better off in a psychiatric group home where there might not be other frail elderly people he could prey on.