In Michigan the police are NOT required to offer Miranda warnings at any time. Lack of these warnings doesn't mean your case will be dismissed - the only benefit to your case if these warnings are not read, is that certain statements you've made, may not be admissible against you, but this does NOT include statements made during the investigation process, which is usually where most relevant statements would be made.
Although lack of Miranda isn't going to hurt the prosecutor's case much except in the rare case, I always cross-exam the police officer to show that he failed to read my client those rights. Most juries assume that Miranda warnings are mandatory and MUST always be read, and if they aren't somehow rights are being violated and it smells of unfairness. I like a jury to bring to hear that the rights were not offered, and allow them to make of this information what they believe to be its importance.
Most DUI cases in Southfield include multiple police officers, and a prosecutor who is backed by 500 employees at their office. It's not a bad thing for the jury to see this David vs Goliath comparison, which makes the lack of Miranda warnings seem even more unfair.
The content of a defendant’s response provided after an arrest may be held inadmissible if Miranda warnings were not given and the court determines the response is testimonial. Pennsylvania v Muniz, 496 US 582 (1990) (content of answers, showing suspect’s confused mental state, is testimonial and barred by Miranda when obtained after arrest). A suspect’s ability to perform sobriety tests is not testimonial, however, and any physical evidence of impairment, such as slurred speech, is admissible without regard to whether Miranda warnings were given. Id. See §5.29. This is a distinction that police officers should understand in investigating a potential drunk driving arrest.
Although a police officer does not have to give Miranda warnings immediately after stopping a suspected drunk driver, the prosecutor should advise police officers to give Miranda warnings after the formal arrest. Most police officers follow a standard procedure to determine when they should place a suspected drunk driver under formal arrest. If an officer’s preliminary questions to a driver are routine and would be asked during any stop and the officer is not engaging in a subterfuge to avoid giving Miranda warnings, a suspect’s statement during the investigative stop will be admissible.