The Detroit Police Department launched an internal investigation after an officer reportedly showed up drunk to a class teaching cops how to administer Breathalyzer tests, WXYZ reported.

Michigan State Police say the offending officer, whose name was not released, had volunteered to be part of a demonstration on breathalyzer training.

“During that class he volunteered to give a sample and it was determined he had alcohol in his system,” State patrolman Mike Shaw told the Detroit Free Press.

The officer blew a .08, which is the legal limit for a DUI in Michigan.

“The bottom line is that he showed up to work under the influence of alcohol,” Detroit police chief James Craig told WXYZ in Michigan.

The officer won’t face charges since he was not armed and did not drive to the training session, police said.