form a legal standpoint the cop thought you were using an illegal substance so he did have probable cause to detain you and question you. he could even search you if you refused. in that situation playing along was probably the best bet unless you were willing to be cuffed, searched, put in a police car, and possibly taken downtown and charged with some bull****. if you wanted to fight for your rights you coulda gave him your name which is required in most states. after that ask him if you were being detained or if you were free to go. if he does not state which keep asking till you get an answer. if he tells you that you are being detained tell him you reserve your rights and will remain silent. they would take you downtown and eventually release you unless they find a bogus charge to hit you with like loitering, jaywalking, etc. you DO NOT have to answer any question besides giving your name. you CAN remain silent. you CAN ask them questions which they MUST answer. the one asking the questions is in control. if they take you downtown they may confiscate your PV for further testing or harass you in many other ways. if you dont play nice they wont play nice. it may suck to let a police officer abuse your rights but in the end you must pick your battles. its not surprising my first post is in a thread like this