MONTREAL - A former heroin addict is suing the RCMP for entangling him in an undercover police operation that left him serving more than eight-years in a Thai jail.

Arguments in Alain Olivier's $47.5-million lawsuit against the Mounties began Tuesday in Quebec Superior Court.

Olivier is claiming the RCMP took advantage of his situation to get him involved in a drug operation in 1989 that resulted in him spending 8.5 years in a Bangkok jail.

He is also arguing the RCMP confused him with his twin brother when recruiting him for the police operation.

Olivier took the stand Tuesday, stressing that while he had been a heavy drug user he was never involved in trafficking.

He related in vivid detail his first encounter with heroin while in Bangkok.

"I knew then it would be my drug of choice for the rest of my life,'' he told the court. "It was like an epiphany.''

Olivier's lawsuit alleges he was eventually entrapped by RCMP officers to buy $10,000 worth of heroin in Bangkok.

An RCMP was killed under mysterious circumstances during the operation.

"What I'll show is that this police investigation was conducted according to the norms,'' said David Lucas, the lawyer representing the RCMP.

Lucas added that Olivier's claims of mistaken identity are irrelevant because it would have only affected the background information the RCMP had on their suspect.