Sign In

Communications of the ACM

ACM News

A Cheating Scandal Has Rocked the Chess World. The 'Chess Detective' Is on the Case

View as: Print Mobile App Share:
Kenneth Regan at home in Amherst, NY.

Regan’s program detects cheating by calculating the odds that a player of a given skill level could pull off a given set of moves.

Credit: Sinna Nasseri/TIME

n an October morning in Buffalo, N.Y., Professor Kenneth Regan sat down in front of his home computer, fired up Zoom, and, after some cheery pleasantries, all but accused a European chess grandmaster of cheating.

A top chess website had asked Regan to look into a series of games that appeared suspicious, and to him, the evidence was clear. "Either you were cheating," Regan told the player, "or this is a major, unprecedented exception to a verdict of my model."

Regan's sunny manner and nonthreatening appearance—like Wallace Shawn with unruly eyebrows and a taste for patterned shirts—belied his message: this guy's career might be over. "I need to put this in your court," Regan said. "Tell me the truth of what happened." The player denied cheating, but Regan said he would still pass his conclusions along to the website. He then signed off, "bye bye!"

In recent years, Regan, a professor of computer science at the University at Buffalo, has become the chess world's go-to independent expert on cheating. The International Chess Federation, known as FIDE, pays him to monitor tournaments, and he consults informally for websites like Since 2020, he's used his proprietary cheating-detection software to analyze more than a million games.


No entries found

Sign In for Full Access
» Forgot Password? » Create an ACM Web Account