Agencies/Trenton, N J

Assemblyman John Wisniewski, the co-chairman of the joint legislative panel leading the investigation, told The Associated Press that some extensions of yesterday’s deadline were granted. The requests of others who were asked to produce documents on a rolling basis were also being considered.

The subpoena returns are likely to be voluminous, as the committee seeks to unravel how high up Christie’s chain of command the order to shut traffic lanes went, whether the operation was meant to punish a Democratic adversary, and if so, why?

Christie has denied knowing about the planning or execution of the operation, and has said he learned that members of his inner circle were involved after an original batch of subpoenaed documents was published on January 8. However, one former loyalist, David Wildstein, indicated Friday there was contradictory evidence to show that the governor knew about the closings as they were happening.

Five people close to the Republican governor and possible 2016 presidential candidate have been fired or resigned amid the scandal, including Wildstein, who is seeking immunity from prosecution.

The AP on Sunday confirmed the most recent resignation, that of Christina Genovese Renna, on Friday. Renna is among those subpoenaed by the legislative panel. She worked directly under Bridget Kelly, the fired deputy chief of staff who set in motion the lane closings with an e-mail to Wildstein saying, “time for some traffic problems in Fort Lee”.

Fellow Republicans, meanwhile, remained adamant that Christie should not resign from his post as chairman of the Republican Governors Association following Wildstein’s latest claim, for which he has so far produced no evidence.

The support from former New York City Mayor Rudy Giuliani and other prominent Republicans put party faithful on the offensive and Wisniewski on the defensive as East Rutherford, N J, hosted the first outdoor Super Bowl in a cold-weather city on Sunday.

Christie, who did not take questions at Super Bowl ceremonies and received a smattering of boos at an event in New York’s Times Square on Saturday, was scheduled to appear on a radio call-in program. He and his family watched the game from a luxury box at MetLife Stadium.

Giuliani, who has been one of Christie’s staunchest supporters, took aim at the credibility of Wildstein and Wisniewski during an appearance Sunday on CBS’s Face the Nation.

Giuliani described Wildstein as a person who “wants somebody else to pay his legal bills and he can’t get them paid unless the governor is responsible”.

He described Wisniewski, a Democrat, as a “guy who’d like to be governor”.

The unannounced lane closures caused massive gridlock in the northern New Jersey town of Fort Lee in September, delaying emergency vehicles and school buses and tying up some commuters for hours over four mornings.

New Jersey legislators are investigating whether Christie aides engineered the lane closures to send a message to the town’s Democratic mayor. The US attorney’s office also is investigating.

Wisniewski also appeared on Face the Nation and defended his role and his previously stated doubts about what Christie knew and when.

“What I’ve said is I have skepticism about the governor’s statement,” he said. “I haven’t said that the governor has responsibility for this. I haven’t said that the governor knew when this was happening.”