TORONTO - The extent to which gaming officials are responsible for keeping gambling addicts out of casinos is at the heart of an eye-popping $5.5-billion lawsuit filed in Ontario by a man who blew through hundreds of thousands of dollars on slot machines.

In his suit against the Ontario Lottery and Gaming Corp., Peter Dennis argues gaming staff allowed him to keep gambling even though he had authorized them to stop him from entering casinos or throw him out if he went in anyway.

Dennis's inability to stay away from the slots had terrible consequences for him and his family, but senior gaming officials said blaming the "self-exclusion program" for his problems was both dangerous and misguided.

"What we find troubling is the belief that this program, when distorted to be something that it isn't, provides hope to real victims that somehow they have found a way not to be responsible for dealing with their own addiction," said Rob Moore, a senior vice-president with the gaming corporation.

"It's quite dangerous and misleading to think that one could transfer the responsibility they have once they've confirmed they have an addiction onto a third party."

Under the voluntary self-exclusion program begun in the mid-1990s, problem gamblers could sign a form authorizing the province's gambling facilities to use their "best efforts" to keep them out or remove them if they sneaked in anyway.

The proposed class action filed in Ontario Superior Court and served on the gaming corporation this week suggests the program was a sham that profited from the most vulnerable gamblers.

According to the unproven statement of claim, Dennis, of Markham, Ont., blew about $350,000 between August 2000 and May 2004 on various slot machines. His health declined, he became depressed and anxious.

After an 11-week, $59,000 binge, he signed a self-exclusion contract at Woodbine Racetrack on May 23, 2004. Officials took his personal information and photograph.

Nevertheless, he continued going into gaming facilities and gambling, leading to another $200,000 in losses.

Ultimately, lenders foreclosed on his two houses and he was fired from his job at a data-management company for failing to pay back money he borrowed from a client.

"Throughout the precipitous deterioration of the welfare of Dennis and his family members, the (gaming corporation) enriched itself at the Dennis family's expense, contrary to its contractual obligations under the self-exclusion contract and other duties," the suit asserts.

Among other things, the suit alleges, the corporation was lax in allowing people on the list in, failing to train staff properly to enforce the program, and not implementing technology to detect those who sought entry anyway.

About 12,000 people have signed onto the program. Staff remove between 600 and 800 of those a year and the gaming corporation said it was experimenting with new technology to help better detect those on the exclusion list.

Still, Moore said, the program was never meant to turn gaming staff into detectives but rather to allow addicted gamblers to take a self-help step by having them acknowledge their problem.

"To presume that this one program is designed as a policing program to keep people out is just wrong," Moore said.

"It was not in its intent, design or its execution a commitment for us to exclude people or to stop people from coming into our facilities."

The suit, filed on behalf of Dennis and his wife Zubin Noble, seeks billions in general, special and punitive damages on behalf of those gamblers who signed on but were nevertheless managed to keep gambling.

Dennis could not immediately be reached for comment.

Moore said the suit highlights the "real and tragic" circumstances associated with gambling addiction.

"Bad things happen to people's lives when they lose control . . . and the materials that are filed as a result of this are tragic and quite alarming," he said.

"I don't want to dismiss those as frivolous because it's not; they're real circumstances and that's why we have a commitment to this."