MONTGOMERY (AP) — The owner of a Dunkin Donuts store in Montgomery, Alabama, has accused an Alabama Ethics Commission investigator of abusing their power.

The Montgomery Advertiser reports Damon Dunn filed a complaint with the commission last week. Investigator Byron Butler filed a discrimination complaint against the store, saying that it was charging black customers more for coffee flavoring. Both men are black.

Dunn says it was an unfounded complaint and Butler later threatened to make problems for the business. He says Butler also didn’t identify himself as a commission investigator before having an employee give a recorded statement in which she recited her personal information including her address.

The commission has 180 days to determine whether probable cause exists for the complaint. An extension may be granted.