Can you be charged? Yes - it does not take much to charge someone with DUI. Will you be charged? Not likely. If you were going to be charged it would have done by now. Once a person is cited by the police for any crime other than a minor traffic violation, a prosecutor (the state's attorney) reviews the evidence and determines what charges to file in court. I cannot imagine a prosecutor who would file a DUI charge based upon the facts of your case. I think you are just lucky he let you go. Use it to your benefit - next time you have a few drinks don't put yourself in that situation - sounds like you used your get out of jail free card!
Although it may be possible to get charged, based on what you wrote, very unlikely (and at this point without BAC levels, no refusal issue, and the fact that he let you go, they wouldn't have much ogf a case against you).
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