The attorney for David Wildstein, a former Chris Christie appointee, tells members of a New Jersey State Assembly committee why his client is pleading the fifth. Later, the committee votes to place Wildstein in contempt.

An appointee of New Jersey Gov. Chris Christie at the center of an apparent plan to engineer a monster traffic jam as an act of political payback was held in contempt Thursday after he refused to answer questions from state lawmakers.

The appointee, David Wildstein, invoked the Fifth Amendment, which offers protection against self-incrimination.

“On the advice of counsel, I assert my right to remain silent,” he said repeatedly at the hearing, convened by the transportation committee of the state Assembly.

The committee is investigating why lanes that funnel traffic from Fort Lee, N.J., to the George Washington Bridge were closed in September, resulting in days of gridlock. Emails published Wednesday by The Record newspaper and other news organizations show Wildstein mocking concerns that school buses were stuck in the mess.

Assemblyman John Wisniewski, the Democrat who chairs the committee, disputed that Wildstein had the right under state law to decline to answer questions. The committee voted to hold him in contempt, a misdemeanor.

The chairman asked Wildstein questions anyway — including about an email from Christie’s deputy chief of staff to Wildstein last August that said: “Time for some traffic problems in Fort Lee.”

Wildstein declined to answer every time, saying either himself or through his lawyer that he had a constitutional right not to.

Wildstein, who went to high school with Christie, was director of interstate capital projects for the Port Authority, the agency that runs the bridge. He resigned in December, saying that growing questions about the traffic jam had become a distraction.

The mayor of Fort Lee, Mark Sokolich, a Democrat, had declined to endorse Christie, who is believed to be considering a run for the Republican presidential nomination in 2016 and who has crafted an image of transcending partisan politics.

In one email published Wednesday, Wildstein refers to the mayor, who is of Croatian descent, as “this little Serbian.”

Christie, at a press conference Thursday morning, apologized to the people of New Jersey and said he was embarrassed by his staff. He fired a top aide, Bridget Kelly, and said that she had lied to him about the bridge fiasco.

He also played down his relationship with Wildstein and said that they were not friends in high school.

Earlier in the day, Wildstein lost a bid in court to avoid testifying before the state committee. His lawyers had argued that the committee was exceeding its authority, that Wisniewski had a conflict of interest, and that there were questions about the validity of Wisniewski’s signature on subpoena papers.

At the hearing, one assemblyman, Thomas Giblin, went out of his way to praise Wildstein’s reputation and encouraged him not to be a “fall guy.”

“You deserve better,” Giblin said. “You have a reputation that precedes you here today, and I think you want to build on that reputation by being candid with this committee. All we’re looking for is some type of solutions and answers.”

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