EXCLUSIVE: Top lawmaker leading 'Bridgegate' probe blasts Christie's claims that he knew nothing of the scandal as 'not believable' and says the public has seen 'just the tip of the cover-up'

NJ Assembly Deputy Speaker John Wisniewski said Christie is either 'a governor who can’t manage his staff or one who isn’t telling the truth'

He trashed the governor's presumed presidential aspirations, saying he can't even be trusted to run the George Washington Bridge

It's inconceivable, he insisted, that a 'hands-on' leader like Christie might 'suddenly have a senior member of his administration go rogue'

A long-time NJ political operative said Thursday that Christie political aide Bill Stepien was likely the shot-caller behind the bridge scandal

The insider added that Christie's deputy chief of staff, Bridget Kelly, was loyal to Stepien and may have taken orders from him

Kelly's childhood friend told MailOnline that she was 'scapegoated' and called it 'a disgrace ... that she's the only one with egg on her face'



Port Authority appointee David Wildstein refused to answer questions during a state assembly hearing, exercising his Fifth Amendment right

Wisniewski described Wildstein's silence as 'the tip of the cover-up'

A US Attorney has opened a criminal investigation after the punitive traffic snarl-ups caused by the bridge plot led to emergency vehicle delays

New Jersey Assembly Deputy Speaker John Wisniewski told MailOnline on Thursday evening that Republican Gov. Chris Christie is 'not believable,' and claimed a staffer who pleaded the Fifth during a 'Bridgegate' hearing represents 'just the tip of the cover-up.'



Christie, said the lawmaker leading the probe into New Jersey's most improbable scandal since the last New Jersey governor was caught up in one of the largest bankruptcies in U.S. history, is either 'a governor who can’t manage his staff or one who isn’t telling the truth.'



In an exclusive interview with MailOnline, the Democratic assemblyman said he was unimpressed with the governor's claim that he first learned Wednesday morning about a political payback plot involving his most trusted staffers and traffic entering the George Washington Bridge.

'It strains credibility,' he said, 'that a governor who is as hands-on as he is would suddenly have a senior member of his administration go rogue like this.'

Wisniewski chaired an unusual public hearing Thursday afternoon in the state's capital city of Trenton, which saw a former Christie transportation appointee invoke his Fifth Amendment right against self-incrimination by refusing to answer questions.

That one-time official, David Wildstein, was implicated in a plot to snarl traffic in Fort Lee, N.J. in retaliation for the refusal of the town's mayor, Mark Sokolich, to endorse Christie's 2013 re-election bid.

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Garden State circus: Chris Christie fended off questions about his management on Thursday, taking responsibility for the bridgegate episode but blaming specific staffers who have now been fired

Christie, a possible Republican White House contender, took responsibility for the bridge scandal on Thursday, while announcing that he had fired a top aide

Right hand woman: Bridget Kelly was close to the New Jersey Governor and critics of Christie say she would not have done anything without taking orders

New Jersey Democratic Assemblyman John Wisniewski told MailOnline that Republican Chris Christie is either 'a governor who can't manage his staff or one who isn't telling the truth'

Sokolich slammed Wildstein directly Wednesday on MSNBC.

'David Wildstein deserves an ass-kicking,' he exclaimed. 'Sorry, there, I said it.'

Wildstein resigned his post with the New York New Jersey Port Authority in December.



I n a raft of emails and text messages published by news outlets on Wednesday, he appeared to be orchestrating the plan along with Christie deputy chief of staff Bridget Kelly and top Republican political consultant Bill Stepien.



A day later Christie dismissed Bill Stepien, his former campaign manager, who earlier in the week seemed destined lead the state's Republican Party. Stepien also lost a lucrative consulting deal with the Republican Governors Association, which Christie leads.

The New Jersey governor also fired Kelly.

' I terminated her employment because she lied to me,' Christie said. 'I am embarrassed and humiliated by the conduct of some of the people on my team.'

Wisniewski seemed to roll his eyes through the phone as he spoke to MailOnline.

'This is the takeaway,' he explained: 'Chris Christie can’t be trusted to run the George Washington Bridge. He certainly can’t be trusted to run a country.'

A long-time New Jersey political operative told MailOnline that Kelly first worked with Stepien, and was apprenticed to him, during Christie's re-election campaign. She took orders directly from him, said the insider, who requested anonymity, making her the tie between the Christie administration and the state's Republican political machine.

Grim: Christie's staff listen sullenly to his press conference hours after he fired a trusted co-worker



Betrayed: Bridget Anne Kelly, Christie said, lied when she was asked whether there was any truth in rumors the bridge closures were arranged

Contempt: David Wilstein faces the cameras before taking the Fifth at a state assembly hearing into the scandal

What me? Christie emerges from a personal meeting with the Fort Lee mayor where he apologized to him

Stepien's job, the source said, 'was to keep the governor's fingerprints off of things,' and Kelly's 'was to put plans into action.'

'If she pulled the trigger on all of this, it was on Bill's urging. He really trusted her.'

Wisniewski , who chairs the New Jersey Assembly's transportation committee, subpoenaed thousands of pages of records from Wildstein, who refused to answer questions Thursday.

He predicted that his committee 'will be issuing subpoenas for Ms. Kelly, for Mr. Stepien, and probably for others as well.'

'We’ve never had a hearing where someone took the Fifth so much,' Wisniewski said of Wildstein's turn on the hot seat.

'I mean, some of the questions were just about figuring out who a text message was from, or who it was sent to. That's hardly the kind of thing that creates legal liability for anyone.'

'David Wildstein is just the tip of the cover-up,' he claimed, referring to Christie administration officials' early explanation for the September traffic backups as part of a study aimed at determining how many toll booths were needed in Fort Lee.

'It’s very clear when you look at the documents that he among others engaged in enormous efforts to come up with a cover story for all of it, and to delay responses to Mayor Sokolich about what was happening.'



Nothing on me: Christie departs his press conference after insisting he knew nothing and telling a reporter who asked him if he had considered resigning: 'That's a crazy question'

Fall woman: Friends of Kelly told MailOnline that they believe she was deliberately made the 'scapegoat'

'Sad': Christie said he was disappointed in his staff's actions, but claimed it was a measure of leadership to act ruthlessly when you discover something had gone wrong

To support his theory that a cover-up likely reaches the top of the state's executive branch, he cited past hearings where Christie administration officials canceled their testimony at the last minute.

'We've had state officials tell us shortly before they were scheduled to testify in committee meetings that the governor's office told them not to participate. That happens with this governor,' Wisniewski recalled.

'So we know from our own experience as legislators that this governor reaches into his departments, tells commissioners what to do, what they can say. And now he expects us to believe that Bridget Kelly closed down three lanes leading to the George Washington Bridge on her own without his input? It’s just not believable.'

Christie said Thurdsay that he was 'heartbroken,' 'blindsided,' and 'embarrassed and humiliated' as the story broke. 'I had no knowledge or involvement in this issue, in its planning or its execution ,' he said during his lengthy press briefing.



Wisniewski was skeptical.



'W hile there’s no direct documentary evidence that he’s lying,' he said, 'it strains credibility.'

Fort Lee, New Jersey, Mayor Mark Sokolich (R) said former Christie aide David Wildstein 'needs and ass-kicking' The SEC's inquiry follows several other probes launched after the so-called Bridgegate scandal, in which operatives loyal to Christie's administration are accused of causing traffic jams on the George Washington Bridge in September in retribution for a New Jersey mayor not endorsing Christie's re-election

Bill Pascrell, a New Jersey Democratic member of Congress whose district includes Fort Lee, agreed in an interview with the Bergen County Record that Kelly was likely following an order to orchestrate the bridge traffic shutdown.



'I don't know who the person is that gave the ultimate order,' said Pascrell. 'This did not, the young lady did not just wake up one morning – when you see the emails – she didn't just wake up one morning and decide "let's screw up the traffic in Fort Lee.'"

MailOnline spoke with a childhood friend of Kelly, who lamented her 'bad day at work.'

'It's a disgrace what's happening that she's the only one with egg on her face,' she said of the now-former Christie administration official.

'I believe this story is much more multifaceted than just Bridget Kelly. My friend has been scapegoated.'

Bridget Kelly kicked off the traffic shenanigans with a gleeful email to Port Authority official David Wildstein on August 13, subpoenaed documents show

New Jersey Assemblywoman Loretta Weinberg (R) said criminal charges could be coming in the Christie 'bridgegate' scandal

Wisniewski also found unconvincing Christie's claim during his Thursday morning press conference that his team had no motive to target Sokolich for revenge.

The mayor, Christie told reporters, 'was never mentioned to me as somebody whose endorsement we were even pursuing. ... So part of this is, I never saw this as political retribution because I didn't think he did anything to us.'



But Wisniewski said there was 'clearly a political motive' in the bridge shenanigans.

'I’ve been told by people that there were political emissaries from the governor who did ask the mayor for an endorsement, ' he told MailOnline, 'and he demurred.'

And Fort Lee is an important Democratic stronghold, he added, with other political comings and goings beyond the gubernatorial race.

'Bergen County was an important spot for county races and statewide legislative races. This might have been about on of them,' he speculated.

Christie met with Sokolich in Fort Lee for 45 minutes on Thursday afternoon, offering the apology that he promised during his morning press event and later calling it 'a very warm and productive meeting between me and the mayor.'

Asked what he said, Christie added: 'I apologized. That’s what I came here to do.'

Texts between two Christie aides depict a callous attitude toward the traffic chaos they caused, including a swipe at children of voters who supported Christie's gubernatorial candidate, Barbara Buono

Not-so-EZ-Pass: When three toll lanes originating in Fort Lee were suddenly forced to merge into one in September, traffic snarled for a week until authorities in New York City reversed the New Jersey officials' order

Sokolich accepted the apology and added that his 'biggest concern is that we make sure that this never, ever, ever happens again in the future.'

'We were unconditionally provided with that assurance,' the mayor said.



Assemblyman Wisniewski said his committee staff would begin releasing the full collections of subpoenaed documents – 'somewhere between 3000 and 5000 pages' – on Friday morning, beginning with the material provided by Wildstein.

GOP leaders at the national level watched the drama unfold with an eye toward the 2016 race, with the governor's supporters keenly aware that his performance will determine whether he is considered presidential material.



Christie is set to be inaugurated for a second term as governor on January 21.

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