You don't have to be read your rights in order to be properly arrested, even though they do it that way on TV all the time. An officer is required to read someone their rights before questioning them while they are in custody.
Your son should not try to defend the DUI on his own. An experienced defense attorney can analyze his case, identify any defenses that may be available, and negotiate with the prosecutor on his behalf. If you need a referral, feel free to call. I can give you the name of an experienced Cook County DUI attorney. 1-312-346-5320.
Your son's public defender has already or will soon issue a subpoena for the video footage as we speak. It's part & parcel in every DUI defense. The fact that Miranda wasn't read doesn't have any impact on his labs or field sobriety - Miranda only applies to incriminating statements made subsequent to being detained. That's it.
Keep in mind DUI charges are two-fold, first there's the criminal trial, and concurrently there's the administrative hearing to get his license back. His PD doesn't handle the admin portion; he'll need a private attorney for that, presuming he wants to drive legal for the next year.
Make sure to obtain a lawyer who practices in DUI. If he is convicted, your son will lose his driver's license for a minimum of 2 years. During the first year, he cannot apply for any type of restricted license. These are special rules for those under 21.
Videos are often turned over as a part of the case. If not, it can be subpoena'd. However, you should know that a person's failure to be 'Mirandized' id not a defense to a DUI. Rather, such a failure would only cause confessions to be suppressed. It sounds to me like you need a lawyer who can advise you of the law in this area, and that it would be dangerous to proceed without one.
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