NEWARK, N.J. (CBSNewYork/AP) — The legislative committee looking into the lane closure scandal on the George Washington Bridge has received a federal subpoena involving a former top Port Authority of New York and New Jersey official.

As WCBS 880’s Peter Haskell reported, the subpoena asks for audio and video recordings of testimony by Bill Baroni, the former deputy executive director of the Port Authority, who was appointed by New Jersey Gov. Chris Christie.

Exactly why the U.S. Attorney wants the recordings is unclear, Haskell reported.

The latest subpoena connected to the Bridgegate scandal follows others going to Christie’s reelection campaign.

“It seems to indicate, at least to me, an increased level of activity,” said Assemblyman John Wisniewski (D-Sayreville), co-chair of the legislative probe.

Baroni testified before the legislative committee that the lane closures were for a traffic study. But documents released a year ago suggest they were politically motivated.

Democrats called the lane closures political retribution against Fort Lee Mayor Mark Sokolich for not supporting Christie’s reelection bid in 2013.

But a report commissioned by the Christie administration determined there was “not a shred of evidence Gov. Christie knew anything about the GWB lane realignment beforehand,” its lead attorney, Randy Mastro, said in a statement.

Christie fired his deputy chief of staff, Bridget Kelly, over the scandal. His Port Authority of New York and New Jersey appointee, David Wildstein, resigned.

Kelly sent an email to Wildstein reading, “Time for some traffic problems in Fort Lee.” That message apparently triggered the lane closures.

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