Mike , I have a acquaintance that had a similar thing happen to him . He buys and sells vehicles and is also a casual Pot smoker . He got stopped while driving a van he had just purchased with his dealer plates on it and the cop noticed a half smoked joint in his ashtray . They arrested him , searched the van and behind the spare tire they found an ounce of pot that was so old it was all mold and mildew obviously hidden there by a previous owner . Of course his lawyer got him out of it with a slap on the wrist but shit does happens .
Jack