Investigators say Alfredo Borodowski, 49, flashed a fake badge at the 24-year-old woman while driving his Toyota Camry in Mamaroneck Wednesday morning and ordered her to pull over.
Instead, she called the real police.
Borodowski, of White Plains, was apparently upset that she was driving too slow when they were in a school zone.
He is now charged with first-degree criminal impersonation.
He was arraigned Wednesday and released. He is due back in court on July 11.