Ruben Turner, 30, used his finger to write the word "help" backwards in the condensation on the window; however, he wasn't discovered until Tuesday morning when officers reported for duty at the city's Southeast Precinct station and heard him yelling.
"Turner ... told the officer that he'd accidentally locked himself inside the back of the police car after deciding to sleep in the car overnight," the Portland Police Bureau said in a written statement. "The car had apparently been left unlocked overnight."
The station is not manned 24 hours so Turner had to wait and wait and wait until the day shift arrived.
Turner was charged with criminal mischief among other things. Officers said he rifled the car's glove box and tore up the headliner before managing to crawl into the secured back seat where he became stuck.