A Cook County judge Thursday vacated felony convictions for 15 defendants who claimed they were framed by disgraced Chicago Police Sgt. Ronald Watts, following a landmark decision by the State’s Attorney’s Office to toss aside a string of cases over allegations of police misconduct.

With 10 of the defendants standing in the courtroom, Chief Criminal Courts Judge Judge LeRoy K. Martin approved a motion by prosecutors to throw out a total of 18 cases against 15 men who were arrested by Watts and members of a tactical team that operated in the Ida B. Wells housing projects.

After the hearing, attorney Joshua Tepfer said the move by State’s Attorney Kim Foxx marked the first “mass exoneration” in the history of Cook County.

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“It’s an extraordinary sign of what’s going on in this county and this city to have a…crucial law enforcement entity take this step and overturn all these convictions in recognition of a systemic problem of police corruption,” he said.

Mark Rotert, head of Foxx’s Conviction Integrity Unit, said the office could not stand behind the cases after reviewing claims brought by the 15 defendants, who said Watts and his fellow officers planted evidence and filed false reports.

“In these cases, we concluded, unfortunately, that police were not being truthful and we could not have confidence in the integrity of their reports and their testimony,” Rotert said. “So in good conscience, we could not see these convictions stand.”

The decision by the state’s attorney to toss the convictions was first reported by Sun-Times columnist Michael Sneed.

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Lawyers for the University of Chicago’s Exoneration Project two months ago filed a petition to throw out convictions in 18 cases brought against the 15 defendants, mostly drug charges in which they claim they were shaken down by Watts and officers under his command.

Watts and fellow officer Kallatt Mohammed in 2013 pleaded guilty to stealing $5,200 from an FBI informant. Two of the men exonerated Thursday were currently jailed on unrelated cases, Tepfer said.

Watts could not be reached for comment.

The hearing, coincidentally, came during a whirlwind 72-hour span that had seen two men released from prison after spending decades in prison based on claims they had been framed by other Chicago Police officers.

Former Chicago Police Sgt. Ronald Watts leaves the Dirksen Federal Building on Oct. 9, 2013, after receiving a 22-month sentence after being found guilty for his role in an FBI sting operation. | Sun-Times file photo

Tuesday, prosecutors dropped their case against Arthur Brown, who had spent 29 years in prison for a deadly 1988 arson fire, and Wednesday, Jose Maysonet walked out of the Cook County Jail after spending 27 years jailed for a 1990 double-murder. The State’s Attorney’s Office said they were troubled by discrepancies in the evidence in Brown’s case. Prosecutors said they were unable to move forward with their case against Maysonet after five CPD officers refused to testify under oath about allegations Maysonet was beaten into confessing.

Police Board President Lori Lightfoot said Thursday the fact that “so many Chicago Police officers asserted their Fifth Amendment rights” to avoid testifying under oath is a “horrible, unacceptable circumstance that must be addressed immediately.”

She added: “All of the efforts that we are are trying to undertake to reform the police department and bridge the gap between police and the community will be negatively affected if officers who commit crimes and admit to it are able to walk away with impunity.”

Foxx, who took office last year after beating incumbent Anita Alvarez with a campaign that pledged to reform the county’s criminal justice system, had said earlier this year her office was reviewing cases handled by Watts’ team.

The felony charges wiped out yesterday typically were drug cases, convictions that landed the defendants in prison for a few years. Leonard Gipson, 36, was convicted twice on charges in which Watts planted drugs on him, after, Gipson said, he refused to give cash to Watts.

“Every time I ran into him, he put drugs on me,” said Gipson.

Leonard Gipson is among the 15 men whose convictions were tossed on Thursday. He said corrupt cop Ronald Watts planted drugs on him, after Gipson refused to give cash to Watts. | Andy Grimm/Sun-Times

“Everyone knows, if you’re not going to pay Watts, you’re going to jail.” Gipson, who had claimed in court that he’d been framed, and only pleaded guilty after a judge ruled he had no proof Watts had planted drugs on him. Gipson also had filed a complaint about Watts with the CPD, which went nowhere.

“Everyone knew what he was doing.”

Since filing his petition in April, Tepfer said he has been contacted by dozens of others who have made similar allegations against Watts. Tepfer has estimated hundreds of cases handled by Watts and officers who reported to him, are bogus. Watts and his subordinate officers routinely hung felony cases on residents of the complex as retribution against those who resisted when he demanded cash, or if they filed complaints against him. Watts’ officers would plant drugs and falsify reports to make the charges stick, Tepfer said.

Tepfer and other civil rights lawyers had pressed Alvarez, to appoint a “special master” to consider clearing defendants in possibly hundreds of arrests made by Watts and officers who worked in his unit. Rotert declined to give details on the “exacting process” of reviewing cases.

“Cases have to be evaluated individually and on their own facts. I’ll take a look at any case that anyone wants to bring that they believe is affected by corruption,” Rotert said. “But rather than pre-judge it, I’m going to tell you what I think after I’ve reviewed all the evidence.”

The latest blow to law enforcement in Chicago comes at a time when Mayor Rahm Emanuel is investing $27.4 million in police reform.

The mayor finalized that 2018 investment without consulting Illinois Attorney General Lisa Madigan, with whom he is supposed to be negotiating a consent decree culminating in the appointment of a federal monitor to ride herd over the Chicago Police Department.

“When you have such high-profile actions by officers who acknowledge criminal conduct, it’s a significant blow. There’s no sugar-coating it,” Lightfoot said.

“These officers bring shame upon their fellow officers who work very hard to do their jobs the right way in compliance with the Constitution and the law.”

Contributing: Fran Spielman