More than six years after a mysterious multi-day traffic jam at the George Washington Bridge, four years after the resulting Bridgegate scandal helped to blow up former New Jersey Governor Chris Christie’s presidential chances, and three years after former Christie appointees Bridget Anne Kelly and Bill Baroni were convicted for their role, the three reunited, in a way, at the U.S. Supreme Court on Tuesday.

That’s because Christie made a surprise appearance to observe Tuesday’s hearing, sitting alongside his wife, Mary Pat, and directly in front of Kelly and her attorneys, in the public seating section of the courtroom. Baroni was on the other side of the ornate room, and appeared to be shaking his head in shock that the former governor resurfaced to take in an hour of oral arguments about the case that sunk his political career.

Listen to Matt Katz's report from Washington D.C. on WNYC:

It was the first time Christie and Kelly has seen each other since he fired her in 2014, after the release of her “Time for some traffic problems in Fort Lee” email that blew the scandal wide open.

“It’s been a long six years,” Kelly said after an hour of oral arguments on the convictions. “I hope [Christie] had a harder time seeing me than I had seeing him.”

The fact that the lane closure scandal was even before the Supreme Court was a surprise in itself -- so much so that Baroni reported to prison to begin his 18-month sentence last spring, assuming the high court wouldn’t take the case. He was released on bail in June when the Supreme Court opted to hear the matter, and he won’t have to return if the justices rule to throw out the convictions. After the hearing, Baroni thanked the inmates he served with for their support: “For every day that I was there they never let me stop believing, never let me give up. And sometimes people forget them. And they are not forgotten today.”

Kelly herself was on the verge of leaving for her 13-month prison sentence when the Court intervened. Her ex-husband was making plans to move into her house in order to take care of their four children.

Most of the justices seemed skeptical of the convictions, peppering the deputy solicitor general from the Trump Administration, which inherited the case from President Obama’s Justice Department, with questions about how the pair could be convicted on fraud charges if they derived no personal gain from the lane closures. The resulting traffic was intended to punish the Democratic mayor of Fort Lee, at the foot of the bridge, with gridlock in his town after he failed to endorse the Republican governor’s 2013 reelection.

Christie was never charged with a crime, but testimony at trial indicated that he was aware of the lane closures from at least the time they began on the first day of school in 2013. School buses and emergency vehicles were gridlocked every morning for four consecutive days.

Bill Baroni outside the Supreme Court on Tuesday.

Another question the justices repeatedly returned to was whether Baroni even had the authority to close the lanes. The feds say he didn’t, and that the lie about the reason for the lane closures -- a bogus traffic study -- constituted fraud. Baroni’s attorney, however, countered that as the top New Jersey official at the Port Authority he could control access to the bridge, and even if his motives were less than pure, it fell into the category of rough-and-tumble politics, not criminal fraud.

Justice Elana Kagan asked if it mattered what the purpose of the lane closures was. “Would it or would it not make a difference if the defendants here, rather than doing everything that they did for a political reason, if they had done it to make their commutes easier or their families' commutes easier?” she asked.

Yaakov Roth, Kelly’s attorney, said no, it would not be fraud, because property was not obtained. Justices brought up the hypothetical example of a mayor and his snowplows: The attorneys for the defendants said that a mayor who chooses to plow the part of town where he lives -- instead of the area where his political opponents reside -- is not engaging in a federal crime.

“If you're plowing public road, and you say I want to plow my street first or my neighborhood first, that is not obtaining property by fraud because that is an allocation of resources to a public use,” Roth said. “It's a public use that happens to benefit you, and maybe that was your motive and that's very bad, but it's not obtaining property by fraud.” If it was fraud, he said, normal political activity would be criminalized.

The court has increasingly narrowed the definition of political corruption through a series of recent decisions, and the justices seemed amenable to this argument.

The deputy solicitor general, Eric Feigin, argued that the defendants “committed fraud by telling a lie to take control over the physical access lanes of the George Washington Bridge and the employee resources necessary to realign them.” Tens of thousands of dollars was spent on the fraud, he noted, in the form of salaries for those who worked the tolls and prepared the fake traffic study.

But, the defendants’ attorneys argued, that money did not personally benefit Baroni and Kelly.

The question, then, comes down to what is “bareknuckle New Jersey politics” (to borrow a phrase from Baroni’s brief to the court), and what constitutes illegal behavior that warrants prison time. In a way, the closure of the lanes fit into a pattern of actions that the Christie Administration and the Christie reelection campaign engaged in -- a carrot-and-stick approach to elected officials, wooing them for endorsements by inviting them to breakfasts at the governor’s mansion and giving them the Port Authority’s burnt steel from the wreckage of the World Trade Center to display in their towns.

In a court filing, Baroni even said the $250 million purchase of a terminal in Bayonne by the Port Authority -- which is jointly controlled by the governors of New Jersey and New York -- was a way to help the mayor of Bayonne and get him to support Christie. Those who failed to endorse were punished -- Steve Fulop, the mayor of Jersey City, saw a series of meetings with state officials immediately and contemporaneously cancelled.

But the political arena, not the judiciary, should deal with such behavior, Roth said.

“We have certainly political remedies that...had pretty substantial repercussions here,” he said. Roth never uttered Christie’s name -- in fact the governor, who was repeatedly referred to during the 2016 Bridgegate trial, was not mentioned once as he watched from the audience. But those “substantial repercussions” -- the demise of Christie’s presidential campaign and perhaps his political career -- were readily apparent to the courtroom.

Matt Katz is a reporter at WNYC News covering immigration, hate, and security. You can follow him on Twitter at @mattkatz00.