They can still charge him. Whether they'll be able to convict him, well that's another matter. Have your friend contact the McLean County Bar Association for a list of attorney's that concentrate in DUI defense. Best of luck & hope this helps!
They can charge him, but it sounds like they have a pretty weak case.
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Given the way you have described the facts, they can charge him, but they may not be able to prove him guilty at trial. Of course, I expect that the officer's description of what happenned will be less favorable than the defendant's own version. A weak lawyer can plead anyone guilty. But a strong lawyer is normally needed if someone wants to fight or win a case.
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