An appeal is not a re-trial, rather it is a reexamination of the trial by a higher court in order to make sure the trial was conducted fairly and is free from legal error. An appeal for a drunk driving conviction may serve to lessen the sentence or strike the conviction from the record, which will be beneficial to defendant in the instance of a future drunk driving offense.

An appeal should be submitted as soon as possible following a conviction and sentencing. The amount of time a person has to submit a notice of appeal varies by state but is usually between 10 and 30 days. Appeals are only possible for those cases that went to trial. Those who reach plea bargain agreements normally waive their right to an appeal.

The appeal process starts when the defendant, now called the appellant, requests that the case should be re-tried or re-sentenced because of legal error. Rarely will a case be re-tried. Instead, a higher court, or appellate court, looks at a record of the court proceedings for the drunk driving case. It does not consider new evidence.

Both the prosecution and the defense also submit written briefs to the appellate court. The prosecution argues why the conviction and/or sentence should be upheld. The defense's brief should explain why the conviction and/or sentence is erroneous. The defense usually has an opportunity to respond to the prosecution's brief through a second brief. The appellate court may also listen to oral arguments from both sides before deciding on the appeal.

Although notice of an appeal is required to be submitted very soon after a conviction, the entire appeal process may take many months. However, since a drunk driving conviction must almost always be reported on job applications, and may be detrimental in the event of a future drunk driving offense, the appeal process is a valuable one.