New Jersey Gov. Chris Christie said Thursday he has hired a legal team headed up by a former federal prosecutor to help his administration review an apparent political payback scandal that snarled traffic for days on the George Washington Bridge.

Randy Mastro will lead the team from the firm of Gibson, Dunn & Crutcher, the administration said. The firm will “review best practices for office operations and information flow, and assist with document retention and production,” the administration said in a three-paragraph statement.

The team also will help Christie’s office deal with multiple investigations, including by the U.S. attorney.

The U.S. attorney’s office in New Jersey and the Legislature are looking into a plot that shut down lanes to the George Washington Bridge for four days in September, causing massive traffic jams in the town of Fort Lee. The plot apparently was hatched by Christie’s aides as a political vendetta, possibly because Fort Lee’s Democratic mayor wouldn’t endorse the Republican governor’s re-election.

Mastro was an assistant U.S. attorney who specialized in organized crime cases and led the federal government’s landmark racketeering suit that compelled the International Brotherhood of Teamsters to hold elections and undergo court supervision, the administration said. He also served as a deputy mayor of New York City under Rudolph Giuliani.

His hiring was announced one day after the state Assembly tapped Reid Schar, the former federal prosecutor who won the corruption conviction of former Illinois Gov. Rod Blagojevich, to aid in its investigation. Schar is a partner at Jenner & Block.