A man with a history of exposing himself in public was arrested after cops found him masturbating in front of women at a Paramus doctor’s office, authorities said Wednesday.

Brian Bates — or, as he might be referred to if he were on “Downton Abbey,” Master Bates — was charged with criminal open lewdness for the Friday incident at a Ridgewood Avenue office, according to borough police Chief Kenneth Ehrenberg. Officers went to the medical office for a report of a man exposing himself to patients.

“Upon police arrival, officers found Bates in the bathroom with the door open while masturbating and simultaneously attempting to penetrate his anus with the handle of the toilet bowl scrubber,” Ehrenberg said in a statement.

Bates was taken to New Bridge Medical Center for evaluation after being booked at police headquarters, authorities said.