A man fatally shot at his home in a confrontation with RCMP in Prince George, B.C., was a veteran of the Bosnian conflict who was finally getting treatment for post-traumatic stress disorder, says his family.

Greg Matters was a soldier for 15 years, his sister, Tracey, said on Thursday.

He left the Canadian Forces in 2009 and after he returned to his home town in northern British Columbia it became clear to those who loved him that Matters was suffering from PTSD, she said.

"There was a delay in him getting treatment," said his sister, who returned to Canada from Australia after learning her brother was dead.

'Why wasn't my brother allowed to talk to his doctor, his mother or family friends during the standoff?'—Greg Matters' sister Tracey Matters

"We actually, as a family, suspected he had post-traumatic stress disorder and we sought treatment independently."

About a year and half ago, he began treatment at the Operational Stress Injury clinic in Vancouver, one of nine across Canada funded by Veterans Affairs.

Matters' sister Tracey says she doesn't understand why her brother was shot. (CBC)

"He was just back to the good old Greg that I knew 20 years ago," Tracey Matters said in a telephone interview with reporters. "He was an absolute riot. I loved him to bits.

"He was a decorated veteran suffering from PTSD but was making amazing success; he was improving dramatically."

But on Monday, an RCMP emergency response team was deployed to a rural property near Prince George, in the province's Central Interior, where a confrontation ensued, and 40-year-old Matters was fatally shot by police.

Unanswered questions

His family said there are many questions they want answered about his death, including why police used lethal force on a man on his own property when the family has been told Matters was not armed.

"Why wasn't my brother allowed to talk to his doctor, his mother or family friends during the standoff when this was requested?" she asked. "Why was an emergency response team deployed in the first place?

"And most importantly, why is my brother no longer with us?”

In the hours before the fatal confrontation, Greg Matters sent a series of emails to the local newspaper, the Prince George Citizen, that mentioned his mental health struggles and his military service.

He wrote of a dispute with his brother at his mother's home on the weekend, and a belief that RCMP were out to hurt him.

"This all goes back so much -- the police wishing to hurt me -- why do people want to hurt me -- I did nothing wrong but protect myself and more importantly my mother and property," Matters wrote to the Citizen in an email time-stamped 11:04 a.m. on Monday.

Matters said her brother was taking university courses via correspondence and was planning a trip to Australia to visit her this Christmas.

British Columbia's new Independent Investigations Office is looking into the shooting, and Matters said she has confidence in that investigation.