Federal prosecutors urged the U.S. Supreme Court to uphold the convictions of two former members of Gov. Chris Christie’s inner circle in the Bridgegate scandal — rejecting defense assertions that they were criminally charged over routine political behavior.

The high court is set to hear arguments in the high-profile corruption case in January.

In a brief filed late Friday by the Department of Justice, attorneys for the government reiterated their arguments that Bridget Anne Kelly, who served as deputy chief of staff to Christie, and Bill Baroni, the former deputy executive director of the Port Authority of New York and New Jersey, committed fraud when they conspired to shut down two of three local access lanes leading to the toll plaza of the George Washington Bridge in a scheme of retribution.

The bizarre plan over four days in September 2013 was meant to send crippling traffic into Fort Lee as payback after Mayor Mark Sokolich, a Democratic mayor, decided not to endorse Christie, a Republican, during the governor’s re-election bid.

Christie was never charged with any wrongdoing and denied any knowledge of the plan.

“Kelly and Baroni lied about a traffic study in order to hijack Port Authority resources to gridlock a town, cause maximal harm to its residents, and endanger public safety,” federal prosecutors wrote in their 53-page brief. “That was both outside their authority and repugnant to the goals of safe and efficient transportation.”

They said the two lied to order Port Authority employees to create a bottleneck at the toll plaza of the world’s busiest bridge, and send a message to the mayor in the midst of a political campaign.

“By telling those lies, and diverting the agency’s resources to serve their own personal ends of inflicting massive four-day gridlock on Fort Lee, Kelly and Baroni committed fraud,” they wrote.

Bill Baroni and Bridget Anne Kelly.

The scheme, which became widely known as Bridgegate, was orchestrated by David Wildstein, a Port Authority political appointee and Baroni’s de facto chief of staff, who pleaded guilty and became a prosecution witness. Baroni and Kelly were both found guilty in November 2016 and sentenced to prison. In return for his cooperation, Wildstein received probation.

In their own briefs filed with the Supreme Court earlier this year, attorneys for Kelly argued that the prosecution criminalized what they called routine political behavior, and said that the ordinary anti-theft and anti-bribery statue statutes used in the case had never before been used to pursue political corruption.

“The alleged conduct here was petty, insensitive, and ill-advised. But in our system, political abuses of power are addressed politically,” they wrote.

Kelly was the author of the infamous “time for some traffic problems in Fort Lee” email, sent to Wildstein shortly before the lane closures at the bridge. It was a message that prosecutors pointed to as a smoking gun in the case and was a key piece of evidence used against her. She had testified that she was told the lane closures were part of a legitimate traffic study.

Baroni’s attorneys in their briefs called Bridgegate “a case of bare-knuckle New Jersey politics, not graft.” They said if the government could convict a public official of fraudulently depriving a public agency of money or property simply for employing his agency’s resources “with a concealed political motive,” then the federal government will have free rein to charge and convict officials for all manner of political deals, favors, and rebukes.”

But the government challenged the defense arguments. They said had Baroni actually been empowered to reduce the number of local-access lanes at the bridge, “then their concerns about potentially criminalizing large swaths of routine politics would be relevant. They agreed that neither the concealment of political motives for an otherwise legitimate official act, nor an “insincere justification for an official decision in order to conceal a political motive represented federal fraud.

“But those are not the facts that the jury found. The jury found Kelly and Baroni guilty of fraud because it found that they lied about the existence of a traffic study to obtain authority over lane allocation that Baroni did not otherwise possess,” the wrote in their brief.

The said it was no different than an unauthorized midlevel executive taking a company jet “on a vacation to Monaco by falsely telling the pilot that the CEO has authorized a work trip there.”

The justices will hear final arguments from both sides on Tuesday, Jan. 14 at 10 a.m., according to the court’s docket.

Ted Sherman may be reached at tsherman@njadvancemedia.com. Follow him on Twitter @TedShermanSL. Facebook: @TedSherman.reporter. Find NJ.com on Facebook.

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