Some political insiders are wondering if the two investigations on a traffic jam scandal orchestrated by former aides to Gov. Chris Christie are on a collision course that will ultimately force the New Jersey Legislative Select Committee on Investigation to disband so the U.S. Attorney's Office can do its job.

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"The end product of what we seek to do is different from the end product of what the U.S. Attorney's Office seeks to do," said SCI co-chair Assemblyman John Wisniewski (D-Sayreville). "They are looking potentially at some type of legal action potentially on the violation of either federal or state laws. We are looking at understanding how this could've happened so that we could intelligently put together a reform package that fixes the Port Authority, that fixes the governor's office."

Last week, SCI was dealt a big blow when Superior Court Judge Mary Jacobson ruled in favor of two former aides, concluding that a subpoena requiring them to hand over text messages and emails was too broad.  Wisniewski said his committee will continue do its job in the meantime.

"Our counsel has had conversations (with the U.S. Attorney's Office) and we're comfortable in following his advice that we won't be interfering with the federal investigation," Wisniewski said.

The so-called Bridgegate scandal has been dogging Gov. Chris Christie for months. He launched an internal investigation and the team of lawyers he hired produced a report that cleared Christie of any wrongdoing. That report is viewed by many with skepticism.

In September, access lanes to the George Washington Bridge in Fort Lee were closed without prior notice snarling traffic for four days. Some Democrats believe this was done to punish Fort Lee's Democratic mayor for refusing to endorse Christie's re-election.

One of Christie's deputy chiefs of staff, Bridget Anne Kelly, was fired after an email apparently sent by her went public in which she wrote, "Time for some traffic problems in Fort Lee." Christie cut ties with his two-time campaign manager Bill Stepien after Stepien's involvement in the scandal became clear.