Upholding laws on the road isn’t a job only for cops.

In a video recently uploaded to YouTube, Gavin Seim give a bit of a surprise to a Washington State police officer – when he did an actual traffic stop on the officer to warn him that driving an unmarked police vehicle his illegal.

“Hey the reason I stopped you is I saw this car was unmarked,” Seim said addressing the officer. “Is this a registered unmarked vehicle for undercover work?”

When the officer said it was a patrol car, Seim was prepared.

“Okay, you’re not allowed to have patrol cars that are unmarked. Are you aware of that?”

In Washington State, police are allowed to use unmarked vehicles for special undercover work, but not for regular patrol duties.

Writing in his blog afterwards, Seim pointed out the dangers of having a police officer do patrols and traffic stops in an unmarked vehicle:

“In Washington we have unmarked police vehicles impersonating citizens. If you think it’s not a serious issue, try asking those that have been raped or lost loves ones because of unmarked cars.”

Watch the exchange in the video below: