Family and friends of an Ajax man who died after being shot by police last month are calling for justice.

A vigil is planned for Saturday night to honour Michael MacIsaac, and hopefully draw more attention to police shootings.

The 47-year-old was shot by Durham Regional Police on the morning of Dec. 2, 2013 and died from his injuries the next day.

Ontario's Special Investigations Unit is probing the death and said officers were called to the scene after hearing about a man "acting in a strange manner."

The police watchdog says there was an "interaction" between police and the man, prompting an officer to open fire.

MacIsaac's family said he suffered from epilepsy resulting from a childhood head injury  — a condition that caused him to leave his home in a delirious state that day.

His family describes him as being "a loving husband, a protective brother, a devoted son, a fun uncle and a loyal friend."

"This should never have happened. My brother should be alive today, with us, not needlessly buried," his sister, Joanne MacIsaac, said in a statement.

"Police need to stop shooting first, and asking questions later. We don't know the exact details of what happened that morning but one thing is clear, Michael needed support not bullets."

The family is also calling on the SIU to lay criminal charges against the officers who shot MacIsaac.

It also wants all Ontario police officers to receive training in conflict de-escalation techniques, and be required to use the techniques before resorting to fatal force.

The vigil for MacIsaac is scheduled for 6 p.m. at 201 Williamson Drive West in Ajax, east of Toronto.

With files from The Canadian Press