The feds say Ronald T. Coleman became part of “a circle of trust” when the Chicago cop joined the Drug Enforcement Administration in an investigation targeting the Conservative Vice Lords.

But they say he breached that trust when he tipped off one of the gang’s major heroin suppliers. And Thursday, a federal jury found Coleman guilty of obstruction of justice. Coleman dropped his head when the jury foreman read the verdict. Coleman now faces a maximum of 20 years in prison when he is sentenced on Nov. 15.

The Chicago Police Department said Thursday that Coleman has been suspended without pay.

After more than a year of hunting the Conservative Vice Lords as part of Operation Five Leaf Clover, authorities were poised to execute more than 30 arrest and search warrants in June 2014. Then, federal agents and Chicago police heard nine devastating words on the wiretapped phone call of the drug supplier, Rodney Bedenfield: “We gotta homie that works for the task force.”

“They gonna hit 10-12 houses over there,” Bedenfield was told. “And it’s coming soon.”

Coleman grew up and played basketball on the West Side, right where he wound up working with the DEA on the investigation. When it appeared a man he had played basketball with in high school would be caught up in the probe, the feds say Coleman warned that man’s cousin, who Coleman also knew from high school.

Coleman had allegedly spotted the man with Bedenfield, who over the course of a year had provided the gang with tens of thousands of user quantities of heroin, records show.

Through a chain of phone calls, word of Coleman’s warning trickled back to Bedenfield. On a recorded phone call, an associate told him: “He say whatever ya’ll got going on, he say stop it and he’s like and just clean up. He say cause they got us coming.”

The tip didn’t do Bedenfield much good. Authorities caught him lugging three bags in his car from a home in the 2100 block of South Spaulding to a home one block over in the 2100 block of South Christiana. They searched that house and found what a prosecutor called a “drug trafficker’s starter kit,” including at least five handguns, a rifle, 400 grams of heroin and several pieces of drug paraphernalia.

In the end, Bedenfield wound up with an 18-year prison sentence, records show.