High-profile arbitrator Kenneth R. Feinberg has submitted a friend-of-the-court brief in the litigation backing New England Patriots quarterback Tom Brady’s four-game suspension fight against the NFL over Deflategate.

The AFL-CIO also filed a friend-of-the-court brief on Monday asking the 2nd U.S. Circuit Court of Appeals to reconsider a decision handed down by a three-judge panel in April that reinstated Brady’s four-game suspension.

The circuit court panel ruled in April that NFL commissioner Roger Goodell was within the rights of the collective bargaining agreement to suspend Brady four games after the suspension was first overturned by U.S. District Court Judge Richard Berman last year.

Feinberg helped divide the funds for Sept. 11 and Boston Marathon bombing victims.

Feinberg cited his three decades of experience as an arbitrator and special master and said “the high-profile nature of this case … has serious potential to affect public confidence” in the arbitration process.

“Mr. Feinberg comes before this court not to support the unfettered aggrandizement of arbitral powers for he and his fellow arbitrators — but to caution against it,” Feinberg’s brief states.

Feinberg said in his brief that Goodell “impermissibly exceeded the scope of his authority. But more troubling, he used the vehicle of arbitration as a mechanism to rewrite the underlying bargain between the parties, to the sole advantage of his organization. If this type of bias or capricious notions of industrial justice are upheld, the public should — and will — lose faith in the systems of arbitration and private dispute resolution that have become a parallel component of our justice system.”

Led by former U.S. Solicitor General Ted Olson, Brady’s legal team requested the court rehear the matter en banc, meaning all 13 of the active 2nd Circuit judges will decide whether or not an appeal of their ruling should be heard.

Olson, who has argued before the Supreme Court 62 times — filed the petition before the May 23 deadline passed.

Brady was originally suspended by Goodell on May 11, 2015, for his involvement in the Patriots’ alleged deflation of footballs during the 2015 AFC Championship Game against the Indianapolis Colts, which New England won 45-7.

The Patriots were docked $1 million and two draft picks for the scandal that has come to be known as Deflategate.

The Patriots filed a brief in federal court last week supporting Brady, urging the 2nd U.S. Circuit Court of Appeals to rehear his case.

Patriots owner Robert Kraft did not appeal the $1 million fine and the loss of a first-round pick in the 2016 draft and a fourth-rounder in 2017 as part of the penalties.

If Brady’s suspension is again upheld, he would miss New England’s first four games in 2016 against the Arizona Cardinals, Miami Dolphins, Houston Texans and Buffalo Bills. He would be eligible to return on Oct. 16 against the Cleveland Browns.