The filing of a complaint or other official document by the prosecutor officially starts the drunk driving court case. The prosecutor appears at the defendant's initial hearing before a judge to represent the government with regard to pre-trial release issues like bail. At trial, the prosecutor is allowed to go first and presents the government's case against the defendant. The government must prove each element of the drunk driving charge beyond a reasonable doubt, based on relevant, credible evidence elicited through the testimony of competent witnesses. In DUI cases, the arresting officer is generally one of the key witnesses for the prosecution. The prosecutor also participates in requesting or objecting to jury instructions given by the judge at the end of the trial. The prosecutor may also be called on to defend the government's sentencing recommendation if there is a dispute over the sentence to be imposed.