Drewniak declined to discuss his next career move. He says details about his next job are still being worked out.
His departure comes as Christie lays the groundwork for a possible 2016 presidential run and the state faces serious fiscal issues.
Drewniak is a former reporter whose service to Christie reaches back to the Republican’s days as the U.S. attorney in New Jersey.
Drewniak testified before a grand jury last year as part of an investigation into lane closures at the George Washington Bridge.
He was not a target of the federal inquiry, but his lawyer at the time declined to discuss his testimony before the grand jury.
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