CHICAGO (AP) – A political insider who became one of the government’s key witnesses in the corruption investigation of former Gov. Rod Blagojevich’s administration was sentenced Thursday to 5 1/2 years in prison.

Stuart Levine pleaded guilty to money laundering and fraud charges and could have received a life sentence. But U.S. District Judge Amy St. Eve sentenced the admitted swindler and longtime drug addict to the term prosecutors recommended as part of his plea deal.

Levine didn’t testify at either of Blagojevich’s trials, but prosecutors said he deserved substantial credit for evidence that led to Blagojevich’s convictions. Blagojevich is serving a 14-year prison sentence.

Levine did take the stand at the trials of other Blagojevich insiders, and his testimony about his own sordid past was as disturbing as it was captivating.

The 66-year-old Levine described how he used his position as executor of a close friend’s will to cheat its beneficiaries, including a deaf daughter, out of $2 million. Levine then sent surviving relatives a $1 million bill for his executor services.

He also described using hard drugs over three decades. In the early 2000s, he said he would snort 10 “lines” of a powdered mix of crystal methamphetamine and ketamine — sometimes at binge parties he flew to by private jet.

With acting U.S. Attorney Gary Shapiro watching Thursday’s proceedings — underscoring the investigation’s importance to his office — prosecutor Chris Niewoehner heaped praise on Levine’s work with investigators, saying “Mr. Levine was a historic cooperator.” He said Levine helped convict multiple political officials who deserved to be in “a hall of fame of … corruption.”

Before hearing the sentence, a somber-looking Levine stood ramrod straight as he addressed the judge and professed his “profound remorse and deep regret” for all he had done. His voice cracked as he also apologized to his children. One of his supporters broke down in tears as he spoke.

Before handing down the sentence, St. Eve told Levine, “You are one of the most corrupt individuals this district has ever seen.”

A recent prosecutors’ filing reflected their mixed feelings about Levine, noting he “victimized the public, charities and universities, and individuals, with losses in the multiple millions of dollars — much of which went into Levine’s pockets.”

But they also conceded that Levine “has been one of the most valuable cooperators (for this district) in public corruption cases over the last 30 years.”

“It was Levine’s decision to cooperate that set in motion a series of events that led directly to the government obtaining the evidence and witnesses it needed to prosecute Blagojevich,” prosecutors wrote.

On the stand during the trials of Blagojevich fundraiser Tony Rezko and erstwhile powerbroker William Cellini, the heavyset Levine cut an odd figure — speaking nervously at times and in a high-pitched voice, occasionally looking confused. Levine told jurors he sometimes had difficulty with his memory and conceded it may have been due to decades of drug abuse.

Defense attorneys devoted days to tearing at Levine’s credibility, calling him a habitual liar and a lifelong crook, portrayals Levine barely challenged. Cellini’s attorney, Dan Webb, told jurors Levine was “a whack job.”

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