(AP) Disgraced basketball referee Tim Donaghy told investigators in the NBA betting probe that relationships among officials, coaches and players "affected the outcome of games," his attorney said. The league said the charges were unfounded.

Donaghy's attorney made the assertions in a letter filed in U.S. District Court in Brooklyn on Monday, in which he argued that his client should be sentenced to probation because he fully cooperated with prosecutors and has been undergoing treatment for his gambling addiction.

The attorney also suggested that Donaghy told investigators about the gambling activities of other NBA officials and about a referee that passed "confidential" information to an unidentified coach.

The attorney, John F. Lauro, wrote that the U.S. attorney's office for the Eastern District agreed to plea agreements with other defendants in the case, even though his client told investigators about NBA matters outside of the government's initial investigation. Lauro said the disparity in treatment could not be fully explained because prosecutors have "surrounded this case with a cone of silence."

The U.S. attorney's office said Tuesday it has no comment.

In a footnote, the attorney suggested that the NBA might have "pressured" the attorney's office "into shutting down this prosecution to avoid the disclosure of information unrelated to Tim's conduct."

"The letter filed today on Mr. Donaghy's behalf contains an assortment of lies, unfounded allegations, and facts that have been previously acknowledged, such as the fact that certain NBA referees engaged in casino gambling in violation of NBA rules," said Joel Litvin, the NBA president for league and basketball operations, in a statement. "The letter is the desperate act of a convicted felon who is hoping to avoid prison time."

The veteran referee pleaded guilty last year to felony charges for taking cash payoffs from gamblers and betting on games he officiated.

While citing Donaghy's commitment to his family, charitable activities and positive feedback for his career as a referee prior to his "tragic fall from grace," his attorney said that his client's "aberrant conduct" can only be understood in the context of his gambling addiction, a "crippling disease, which prevented him from exercising complete rational self control."

Lauro wrote that Donaghy is taking steps to get treatment for his condition, including therapy with a gambling counselor and attending Gamblers Anonymous meetings.

"Without a doubt, Tim made significant errors in judgment, but he also tried to right the wrongs of his conduct by assisting the government and seeking treatment for his disorder," Lauro wrote.

Donaghy is scheduled to be sentenced on July 14. By law, he faces up to 25 years in prison, though the term could be much lower under sentencing guidelines.

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