TRAVERSE CITY, Mich. - A northern Michigan police department will launch an investigation after an off-duty officer was seen driving a pickup truck bearing a Confederate flag around a group protesting Republican Donald Trump's election as president.

Traverse City police Chief Jeff O'Brien tells the Traverse City Record-Eagle that an internal review will start Monday to see if any departmental rules were broken.

He confirmed that Officer Michael Peters was in a photo taken from Friday's rally.

O'Brien says officers have a right to free speech, "but also a code of conduct and other internal policies."

The newspaper could not reach Peters for comment.