Here's more from the Ann Arbor News:
Police received a report about 12:30 p.m. that a naked man was sitting on a milk crate behind buildings in the 300 block of West Ann Street. Police found the man, who was shirtless and had his pants down around his ankles. He had a beer in one hand and was masturbating with the other while leaning over a pornographic magazine, reports said. The officer arrested the 50-year-old Ypsilanti man for indecent exposure and charges are pending.