The Lehigh Valley attorney will assume the role Nov. 1.
Current Warren County Prosecutor Richard Burke, in the role since 2012, will take a position within the Office of Public Integrity and Accountability under New Jersey Attorney General Gurbir S. Grewal.
“Jim Pfeiffer has deep roots in Warren County, where he grew up and where he has had a very distinguished legal career," Grewal said.
"His three decades in private practice have included extensive work as both a criminal defense attorney and a municipal prosecutor, and he previously served as a judge in New Jersey Superior Court.
"With his vast legal knowledge and experience, as well as his commitment to the county, Jim Pfeiffer will be an outstanding leader for the Warren County Prosecutor’s Office.”
Pfeiffer was a Superior Court judge in Vicinage 13 -- which covers Warren, Hunterdon, and Somerset Counties -- from 2005 through 2007.
He was municipal prosecutor for Greenwich, Phillipsburg, Allamuchy, Knowlton, Blairstown, Frelinghuysen, Hardwick and Franklin.
"James Pfeiffer is a talented and dedicated attorney who is committed to working for the people of Warren County,” Gov. Phil Murphy said.
"I am confident that Acting Prosecutor Pfeiffer will play an important role in working toward a criminal justice system that treats everyone fairly and impartially."
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