Federal prosecutors couldn’t convince a judge Friday that the boss of a Chicago heroin ring killed three men.

But Domingo “Mingo” Blount is still heading to prison for 25 years because he’s a “dangerous” drug dealer who probably did shoot a rival in the face, U.S. District Judge Gary Feinerman ruled.

Blount had pleaded guilty in November to federal drug charges.

He’s a 39-year-old lifelong offender and member of the Black Disciples street gang who’s been arrested more than 40 times.

Though Blount has never been charged with murder, prosecutors tried Friday to extend his drug sentence by presenting evidence he was also responsible for a trio of murders dating back as far as 1991.

A defiant Blount told the judge he’d sold heroin to “take care of my family, so, yes, I sold some drugs, but killing — I never did it.

“If I did kill, they’d have charged me.”

An eyewitness identified Blount as the killer of Antonio Jones in July 2000, and an informant fingered Blount last eyar in the 2011 killing in Cincinnati of Desmond Jennings, while gunshot residue was found on Blount’s hands after the 1991 murder of Phillip Granberry in the South Side’s former Robert Taylor Homes.

But Feinerman said that even by the reduced legal standard required at a sentencing hearing, there wasn’t enough evidence that Blount committed any of the murders.

He said he did believe Blount attempted to murder Dwight Hamilton, who he allegedly shot in the face in 1998. Blount was charged in that case, but cleared after two key witnesses “suffered inexplicable memory problems,” prosecutors said.

Blount’s attorney, Gerald Collins, urged the judge to sentence Blount to the legal minimum of 20 years saying tacking on extra time would not “make that much difference to society,” but assistant U.S. attorney Sheri Mecklenburg suggested 25 to 30 years was more appropriate.

Feinerman agreed, telling father-of-five Blount he “isn’t going to win any awards for acceptance of responsibility” and that the multiple kilos of heroin he dealt “destroyed the lives of users.”

Blount, who was supported in court by a dozen relatives, waved as he was led away.

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