Longtime Chicago Teamsters union boss John T. Coli Sr.’s nearly three-year tenure as head of a 12,500-member local in Mokena proved lucrative for his son Joseph Coli’s law firm, documents obtained by the Chicago Sun-Times show.

Joseph Coli’s Chicago firm, Illinois Advocates LLC, was paid more than $300,000 by two Teamsters Local 710 funds during the three years his now-indicted father was the labor group’s appointed trustee, U.S. Labor Department records show.

Teamsters International president James P. Hoffa placed the elder Coli, his longtime ally, in charge of the Mokena local in 2014, saying the move was “necessary to correct financial malpractices and corruption.”

Nearly three years later — weeks before Coli was hit with federal corruption charges — the Chicago union boss asked Hoffa to “relieve me of my international duties as trustee of Teamsters Local 710.”

He said he was leaving after restoring “professional service, representation and dignity” to the union local — and for free.

“Throughout the past 35 months, I have not received nor have I sought any compensation for my efforts to repair Local 710,” Coli wrote Hoffa in his June 15, 2017, resignation letter.

But Joseph Coli’s firm was paid $221,468 by the union’s pension fund, and the Local 710 Health & Welfare Fund paid the firm $79,247 during 2015 and 2016, records show — a total of $300,715 during the time his father oversaw the local.

And Teamsters Local 710’s website still lists Illinois Advocates as one of two “recommended workers’ compensation and labor attorneys.”

Next to the description of the payments to Illinois Advocates, the union funds’ yearly reports to the Labor Department say: “Owner is son of trustee.”

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Reports detailing the union funds’ spending in 2017 haven’t been filed yet.

The payments from the Local 710 funds to Illinois Advocates were in addition to millions the firm was paid the past few years by other Chicago-area Teamster groups John Coli Sr. also controlled.

Joseph Coli.

Joseph Coli.

The Sun-Times has reported Illinois Advocates was formed right after Joseph Coli finished law school and immediately began to get business from the Teamsters.

One month to the day after Joseph Coli was admitted to practice law in Illinois in 2012, Park Ridge-based Teamsters Local 727 — which John Coli led from 1992 until his indictment last year — named the then-new law firm “exclusive provider” of legal services for its 9,000 members.

Arms of Local 727 paid the firm more than $8.3 million between 2012 and Feb. 28, 2017, according to the most recent financial reports to the Labor Department.

For decades, John Coli was one of Illinois’ most powerful labor leaders, forging alliances with Mayor Rahm Emanuel, Gov. Bruce Rauner and former Gov. Pat Quinn. That ended last year when federal prosecutors accused him of extorting $325,000 from Cinespace Chicago Film Studios on the West Side, where the hit TV shows “Chicago Fire” and “Chicago P.D.” are filmed.

In his first run for mayor, Rahm Emanuel gets endorsed by John T. Coli Sr., then-president of the Teamsters Joint Council 25, on Jan. 25, 2011.

In his first run for mayor, Rahm Emanuel gets endorsed by John T. Coli Sr., then-president of the Teamsters Joint Council 25, on Jan. 25, 2011. I Sun-Times files

Reached by phone, Joseph Coli hung up on a reporter.

His father’s criminal defense attorney, Corey Rubenstein of Chicago, didn’t return messages. Nor did secretary-treasurer Michael J. Cales or other Local 710 officials.

The deals between Local 710 and Illinois Advocates figured in lawsuits two Local 710 business agents and another staff member filed in 2016 against the local, John Coli and the joint council for all Teamsters groups in the Chicago area. The suits said they were unfairly removed from their positions after John Coli Sr. was made “temporary” trustee on July 30, 2014.

According to documents in the case of former Local 710 business agent Roger Kelley, Coli was responsible for hiring his son’s firm — and the deal wasn’t beneficial to the union.

“Upon installation as Local 710 trustee, defendant John Coli Sr. fired the well-known and prestigious labor law firm Asher, Gittler & D’Alba Ltd. that had decades of experience and knowledge assisting in bargaining defendant Local 710,” Kelley’s lawyer, Nicholas Kreitman, wrote. “Defendant John Coli Sr. instead retained the law firm Illinois Advocates at an equivalent or greater cost to the membership.”

Illinois Advocates also represented Teamsters Joint Council 25, which John Coli Sr. headed, in the lawsuits involving the ousted Local 710 officials.

Court records show three cases were filed against Coli, the joint council and Local 710 — two in federal court in Chicago, the other in Cook County circuit court. Undisclosed settlements in all three cases were reached earlier this year.

Ken Paff, an activist with the national dissident group Teamsters for a Democratic Union, says of Joseph Coli’s work for Local 710 that union members “have to question why this inexperienced lawyer gained all this lucrative business from your benefit funds.

“Coli used the union to benefit his own family,” Paff says. “All the while, Hoffa was treating Coli as a very important Teamster leader and ally.”