You will want to hire an attorney. If you have not already done so make sure you contact the DMV within 10 days of the date of the arrest to schedule a DMV hearing. Failure to do so will lead to a suspension of your license. The fact that your criminal case has not yet been filed does not mean that it will not. It is typical for the DA to fail to file charges by the date given by the police officer. This is not the kind of situation you can resolve on your own.
Get a lawyer, quick. Call your local bar association and ask for the lawyer referral service. They will often set you up for a free or very low cost interview in-person or by phone with one or more lawyers qualified to speak with you personally and give you answers. That may be the lawyer you want to hire. If you can't afford a lawyer, the court will appoint one for you, but you have to appear in court to make that happen.
The DA must be able to prove you were driving. You are ahead of most in this situation as you have a witness who will say you were not the driver, and that he drove. You should consult with a DUI lawyer who knows how to handle these cases.
You are welcome to contact my office, as I practice in the Bay Area. If I am not the right attorney for you I can at least give you a number of other excellent DUI lawyers who practice in your area.
I agree with Mr. Bortel. You have a strong set of facts that work in your favor. With a skilled DUI defense attorney, you may be able to get this case completely dropped.
You should also ask any attorney you talk with about sealing and destroying the arrest record.You must be able to establish that you were factually innocent and it sounds like you may have the facts and witnesses necessary to do this.
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