NEWARK, N.J. (CBSNewYork/AP) – The attorney for one of New Jersey Gov. Chris Christie’s former aides raised questions Friday about the credibility of the prosecution’s key witness during cross-examination in the George Washington Bridge lane-closing trial.

Michael Critchley, Bridget Kelly‘s defense attorney, called David Wildstein a liar Friday, describing the former Port Authority of New York and New Jersey executive as someone who would do whatever it took to further his own interests.

READ MORE: Broadway League Says Vaccine Mandate For Children Under 12 Will Take Effect Dec. 14

Kelly, Christie’s onetime deputy chief of staff, is on trial with former Port Authority of New York and New Jersey executive Bill Baroni. They are facing civil rights and wire fraud charges.

Wildstein pleaded guilty in the case and is cooperating with federal prosecutors.

Critchley noted lies that were told to senior managers at the Port Authority in 2013, when he was planning a series of unauthorized lane closures to send traffic jams into Fort Lee as political retribution against the borough’s Democratic mayor who didn’t support the Republican governor in his re-election bid.

Critchley asked Wildstein whether he inaccurately said the closure was a traffic study. Wildstein called it a false statement, but Critchley said it was a lie.

Wildstein admitted to lying for his own benefit — filling out a job application for the Port Authority position he was already appointed to and adding a bachelor’s degree in political science that he never earned, CBS2’s Meg Baker reported.

Emails reveal Wildstein often told people his title was “the governor’s representative at the Port Authority.” He previously testified that his title — director of interstate capital projects — was completely made up.

First thing Friday morning, the defense told the judge he believes Wildstein has committed perjury with “I don’t know” answers.

READ MORE: CEO Vishal Garg Apologizes For Zoom Firing: 'I Blundered The Execution'

Critchley revisited earlier testimony from Wildstein, who admitted to playing a series of political tricks as a young Republican operative, including taking the late Democratic U.S. Sen. Frank Lautenberg’s jacket before a debate so he would “feel uncomfortable.”

“You know what a euphemism is?” Critchley asked. “You explained it by saying you were an exuberant volunteer. That’s a euphemism. You were a thief.”

Wildstein said he wasn’t “willing to accept that representation” and admitted he made a bad decision.

“At the time I was proud,” Wildstein said. ” … I’m embarrassed by it now.”

Emails also showed how close Wildstein was with Port Authority police union leaders and how they were in on the plot to close the lanes and defend them.

Wildstein also voiced his aspirations for the White House, saying it was well known that he would “love to go to Washington someday if Chris Christie was president.”

Wildstein testified Tuesday that Christie was told about the traffic jam while it was underway and seemed happy about it. Christie has repeatedly denied that and has not been charged with a crime.


MORE NEWS: Innovative Gift Card Program With Cash Bonus Aims to Assist Newark Businesses

(TM and © Copyright 2016 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2016 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)