A geological statistician in Toronto claims to have uncovered flaws in a number of scratch-and-win lottery games, and he's worried that some people may be exploiting them to make a profit.

Mohan Srivastava, a 52-year-old father and consultant, first discovered that he could pick out winning tickets in 2003. A friend gave him a scratch-and-win Tic Tac Toe game as a gag gift.

He won \$3, and by the time he walked to the Petro-Canada near his office to claim the prize, he had a hunch about how the games were made.

If it worked the way he imagined, there would be a pattern of numbers on the face of the card that would allow someone to separate winners from losers, "not with certainty but with a pretty high degree of success," Srivastava said.

In the case of the Tic Tac Toe game, he said the trick hinged on where single numbers, rather than repeating ones, appeared on the unscratched card.

Srivastava tested out his hunch and found some startling results: he could pick out a winning game card with 90 to 95 per cent accuracy.

He chalks up his ability to crack the system behind such games to "a kind of odd combination of skills" -- including knowledge of statistics, computer programming and spatial analysis.

The trick to pinpointing winning scratch-and-win cards depends on the game, Srivastava said, but he believes a number of them can be broken -- and he's tested that theory on at least four varieties of the cards.

In the most recent case, he was featured in Wired magazine and given a stack of 20 "bingo type" lottery tickets. Srivastave picked out six cards he thought were winners.

Although he had never examined that particular game before, he was right on four of them, which was twice as many as should have been the case. Srivastava calculated the odds of that happening by chance were one in 50.

In 2006, he also tried his hand at a Super Bingo game, which he says he could beat with 65 to 70 per cent accuracy. He got similar results from a Tic Tac Toe game in Colorado in 2003.

In all three of those cases, he says that news of his "trick" prompted the game in question to be pulled from store shelves.

Now he's asking Ontario Lottery and Gaming, and their counterparts outside the province, to investigate whether the scratch-and-win tickets in circulation are as secure as they think.

"Being a lottery corporation that's handling billions of dollars, I think they should say, ‘We need to make sure that this is just luck,'" Srivastava said.

The OLG has invited Srivastava to consult with them, but vice president Greg McKenzie said their scratch tickets are fine.

"There's absolutely no indication that there's a problem with our games," he told CTV News.

There have been several instances of proven or alleged abuse of the province's multibillion-dollar lottery system in recent years.

In June, a convenience store owner named Hafiz Malik was sentenced to a year in prison for wrongfully claiming a \$5.7-million prize.

Convenience store clerk Jun-Chul Chung, and his children Kenneth and Kathleen Chung are also accused of allegedly stealing a lottery ticket that later won \$12.5 million.

Last fall, the OLG announced it had introduced something called Data Analysis and Retrival Technology to combat fraud.

With files from The Canadian Press