Failure to read a person their Miranda rights typically does not result in dismissal of a case.
In most cases, a Miranda violation does not lead to dismissal of a DUI case. An officer only has to read you your Miranda rights when you are in custody and being interrogated. Confusingly, courts generally do not require officers to read Miranda rights before asking pre-field sobriety test questions.
When a Miranda violation does occur, the remedy is suppression of that statement at trial for most purposes. However, statements obtained in violation of Miranda can still be used at trial by the Prosecution for impeachment purposes.
While rare, there are situations where a Miranda violation could result in dismissal of a case. For example, let’s suppose that your defense is that you weren’t the driver of the vehicle. If the only evidence of driving is a statement you made, and that statement was made in violation of Miranda, your case could be dismissed.
©NorCal Criminal Defense 2016