I would advise that you NOT "DEMAND" to be allowed to leave. If anything you should state that you are leaving. At that point they will either allow you to leave, or make an arrest. That is not to say that you refuse to sign for a citation, etc. Just once business is completed, you don't need to hang around and give them reason to check further.
I would advise saying as little as possible, keeping any answers short and direct (don't start talking about the wife and kiddies, etc). The more you say, the more apt you are to say something wrong.
I would advise, at the same time,e being "co-operative", "compliant", "respectful" (even if you don't), and even "pleasant". Often, depending upon the reason for being stopped, attitude will make a big difference in how your case is handled.
Oh, and when you leave, whether they are f>On Tue, 08 Feb 2005 13:03:14 -0800, Spike wrote
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