Interesting how you are able to recall this with such clarity after getting your ass kicked. I suspect that you recall this through more than a little bit of bias and have twisted it to suit your point of the argument. It is also interesting that you, like so many others stopped at sobriety check points, question the legal validity of said stops. Also, I doubt that you were "conversational" in your protestations. Having been through more than a few of these check points the cops were never assholes. The cops simply did what they needed to do because morons can't get it through their heads that drinking and then driving kills others and that they are basically selfish fucking assholes for doing it. I have met more than a few bad cops in my many interactions with them. Every time I remained calm and respectful regardless of their inappropriate attitude or actions. Two things happened in all the interactions. One, they calmed down and started to act more rationally. Two, they generally either reduced the infraction or charges or outright let me go with a simple warning or admonishment to deal with my issues ASAP or suffer the consequences if they stopped me again. In a number of cases I was in the car with cuffs on. NEVER EVER did I get pissed or mouthy with them. He escalated, you responded and escalated, you got your ass kicked and charged. Cause and effect. What happened to you is totally fucked up and wrong but it happened. The sad part is that all interactions you have with cops now and in the future are tainted by this and all cops are bad no mater what. Good luck with that in the future, it will not serve you to well. This will all be academic in the future as police departments and police unions are forced to implement body cams.