Jeffrey Thompson. Photo from CSPAN.

The donor behind a shadow campaign to get Vince Gray and other local and federal politicians elected will serve three months behind bars, after a federal judge overruled prosecutors’ request for home confinement.

Jeffrey Thompson pleaded guilty to making illegal donations and cut a deal, under which he couldn’t receive more than six months in jail, to cooperate with the long-running investigation. In a filing last month, the man once secretly called “Uncle Earl” argued that he should only be given probation. Prosecutors asked for house arrest.

A judge disagreed, saying home confinement was too light a punishment for funneling millions of dollars to political campaigns. Over six years, Thompson gave more than $3 million to dozens of candidates, including $650,000 to re-elect Gray. In addition, Thompson has been ordered to pay a $10,000 fine and serve 36 months probation, The Washington Post reports.

Ron Machen, then the U.S. Attorney for the District of Columbia, promised that Thompson’s guilty plea was “only the tip of the iceberg” in 2014. But while the investigation ensnared a former Council candidate (who was sentenced to 60 days in jail) and a former campaign aide (who was sentenced to six months in prison), among others, Gray was never charged with a crime.

Since the investigation was dropped, Gray made a political comeback: beating his one-time protege in the June Democratic primary and vociferously arguing that his treatment by prosecutors and the media was unfair.

According to The Post, the government’s case stalled amid questions of Thompson’s credibility as investigators began asking questions about the age of his sexual partners.