No charges are being laid in the case of an elderly Alzheimer's patient who died after a brutal beating at a Dundas nursing home early this year.

James Acker, 86, abruptly awoke in January to an attack by a second male patient in his 80s — who also has Alzheimer's — at St. Joseph's Villa in Dundas.

Acker, who had been living at the Governors Road long-term care facility for 10 months, suffered head trauma, black eyes, a fat lip and a swollen, bloody face. He died back in April. Acker's family says he endured two bleeds on his brain.

On Monday, police announced that the 83-year-old resident who assaulted Acker won't be charged.

"The investigation revealed that the 83 year-old resident, who was responsible for Acker's death, was residing at the facility due to a medically diagnosed illness that would have prevented him from forming the intent to knowingly carry out a criminal act," a police news release reads.

"Since January 2017, the individual has undergone further medical assessments which suggest he would not be fit to stand trial if charges were laid. For these reasons, investigators have determined it is not in the best interests of the courts or public to charge the 83 year-old resident. He remains in a secure psychiatric facility and is receiving the appropriate medical care for his condition."

Police say detectives also looked into any potential criminal conduct in regards to St. Joseph's Villa and its staff and found there wasn't any.

The Ministry of Health and Long Term Care conducted its own independent investigation, and said in April that the nursing home had failed to protect its residents.

In a report released by the provincial ministry, St. Joseph's Villa was slapped with nine long-term care act violations and was also issued three orders that had to be complied with earlier this year.

According to the Ministry's report, the nursing home didn't act on problematic behaviour shown by Acker's attacker in the weeks leading up to the beating.

Police say none of those infractions warrant criminal charges.

Since the incident happened, Acker's family have demanded changes to Alzheimer's care in the province.

adam.carter@cbc.ca