cop check
Techniques used by prostitutes to determine if a potential customer is an undercover police officer. A technique frequently employed by a prostitute is to request her date to simultaneously touch her breasts or genitals as she touches his.
"Picked up a WSW, about 40, very thin just a few blocks east of Josephine. Did the cop check right away, even wanted to give me “a little taste” as we were driving. So I pulled onto a side street..."