“Using the George Washington Bridge, a public resource, to exact a political vendetta, is a crime,” New Jersey Assemblyman John Wisniewski, who is spearheading the bridge probe, told NBC News on Saturday. “Having people use their official position to have a political game is a crime. So if those tie back to the governor in any way, it clearly becomes an impeachable offense.”

In a news conference on Thursday, Christie denied any prior knowledge of plans to use lane closures on the bridge as political payback against the Mayor of Fort Lee for refusing to endorse his re-election. He said he was “stunned by the abject stupidity that was shown here.”

But Wisniewski said he does not find the governor’s denials credible given the number of his top aides and appointees shown to have knowledge of the matter in thousands of pages of emails and text messages his committee has obtained.

“It’s hard to really accept the governor’s statement that he knew nothing until the other morning,” Wisnieswki said.