Joseph Ponte will resign Friday, a day after Democratic City Council Speaker Melissa Mark-Viverito broke with Mayor de Blasio in calling for Ponte to step down. De Blasio has defended Ponte amid the latest allegations.
Staffers were drafting Ponte's resignation speech Thursday evening, the sources said.
Ponte, whose career in corrections has spanned more than four decades, was appointed commissioner in April 2014. The Marine Corps veteran previously led the Maine Department of Corrections, where he instituted substantial reforms. It was to Maine that the city's Department of Investigation, which investigates city agencies, officers or employees for potential corruption, alleged Ponte drove a city-owned vehicle in violation of guidelines.