NBA referee Tim Donaghy pleaded guilty to betting on games he officiated. But it was never proven that he fixed them—until now. Our two-year investigation and intensive data analysis reveals how he did it, whom he did it with and the millions that flowed from the conspiracy.

the NBA was rocked to its core when news broke that referee Tim Donaghy had admitted to illegally betting on games—including games he himself had officiated. The revelation sent shockwaves through the basketball world and raised uncomfortable questions about the integrity of the sport.

For his crimes, Donaghy was sentenced to 15 months in federal prison. The scandal not only tarnished the league’s reputation but also highlighted how basketball, unlike many other sports, is especially vulnerable to game-fixing. With referees holding immense discretion in calling fouls—actions that are both frequent and subjective—it can be surprisingly easy for a rogue official to influence the outcome of a game, and difficult for outsiders to detect.

After his release from prison, Donaghy insisted in interviews—including with ESPN—that he had never fixed games or manipulated outcomes to win bets. “I was not actually in these games fixing the games and throwing calls to win a bet,” Donaghy claimed. When pressed on whether he had ever influenced the outcome of an NBA game, Donaghy maintained his innocence, saying, “Everybody’s entitled to their opinion, but I can just go back and tell you again that the FBI and even the NBA concluded without a doubt that I did not fix NBA games.”

Donaghy continued to insist that he had always blown his whistle with honest intentions, admitting only to wagering on his own games. In the absence of concrete proof that he had fixed games, the Department of Justice never charged Donaghy with that crime. The NBA, for its part, commissioned its own investigation, which concluded that Donaghy had not fixed games.

When asked about the case, then-commissioner David Stern responded, “We can’t find it, and his fellow refs can’t find it, and as best as we can tell, law enforcement can’t find it. So I accept the prevailing view.”

However, not everyone was satisfied with that conclusion. Phil Scala, the FBI official who led the investigation, told ESPN The Magazine that Donaghy’s claims of never fixing a game “never really flew with us.” Scala maintained that, at minimum, Donaghy’s officiating was “subconsciously tainted by his wagers.” Scala also suggested that NBA executives were eager to move on from the scandal, telling agents that it was “impossible” to fix NBA games due to the many “red flags” that would be raised. “When someone tells you something’s impossible, you know they’re full of it,” Scala said.

While Donaghy admitted to betting on games as far back as 2003, the NBA’s internal investigation only analyzed 17 games he officiated during the 2006–07 season. Of those, only one game—between the Pistons and Nets on December 16, 2006—raised concern that Donaghy’s calls might have favored the team (Detroit) that his associates had picked to cover the spread.

Unsatisfied, ESPN The Magazine conducted its own analysis of all 40 games Donaghy officiated from the time he began working with his co-conspirators until the scheme unraveled. Ten of those games were blowouts and were discarded from the analysis. Of the remaining 30 competitive games, Donaghy’s calls favored the team his partners had wagered on in 23 cases—a staggering 77 percent. In only three games did his calls go against their team, and the calls were even in four games.

Statistically, the odds of this imbalance occurring randomly were calculated at 6,155-to-1.

The Tim Donaghy scandal remains one of the darkest chapters in NBA history, serving as a cautionary tale about the vulnerabilities of sports officiating and the importance of transparency and accountability in professional leagues.