You need to remember that you have rights, and you have defenses. For example, a defendant has the right to demand that criminal charges be dismissed if evidence was unlawfully obtained.
The courts will order that a case be dismissed if the stop of a vehicle by the police violated a defendant's constitutional rights to be free of unreasonable searches and seizures. Other, common reasons for dismissal arise from the failure of a police officer to stop asking questions when a citizen invokes the right to speak with an attorney. The police may have failed to follow national standards in administering field sobriety tests. A chemical test may be ruled inadmissible because of a problem with laboratory equipment or procedures.
In any investigation, police will make mistakes. A competent and diligent defense attorney will require the prosecutor to produce all of the Government's proof, and will challenge the Government's case in court if there is a fight over any point of fact or law.
If the police obtained evidence illegally, the remedy for the court to order that the jury will never hear or consider this evidence. Sometimes, when this happens, a case is thrown out, or, "dismissed in the interests of justice."
A defense attorney also can challenge a proposed DMV license suspension. At an “implied consent” hearing a defense attorney will have the chance to question police officers under oath, shortly after an arrest. If there's a police video, it can be subpoenaed so that you and your attorney can review it at your implied consent hearing.
An experienced and highly-trained DUII specialist will know how – and when – to make the legal motions that force the district attorney to reveal the flaws in the Government's case and may be able to persuade the prosecutor or a judge that the case should be dismissed.