There are several requirements the police must meet in order for their roadblock to be valid. One of the things I always do in every DUI case I defend where a roadblock is involved is to subpoena all paperwork related to the roadblock so I can determine whether or not the police had a right to stop you in the first place. If the officer told you that you were not free to leave and then proceeded to force you to give evidence against yourself, then some or all of that evidence may have been illegally obtained and can be kept out of any trial. I would be glad to talk to you further if you have more questions.
Your case sounds very interesting. It seems as if they may not have enough evidence of impairment to support a conviction. To get a copy of the roadblock procedures, you can start by sending an open records demand to the police department. You really should consider consulting with a DUI attorney. Based on these facts, I would be leery of any attorney who quickly starts talking about the kind of plea deal he can get you. I suggest you consider fighting this charge.
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