An appeal is usually not an opportunity to re-litigate the facts of a case or, in most cases, present new evidence. Instead, an appeal is a chance for a defendant to let an appellate court know about any legal errors made during a criminal case. Examples of legal errors that might be grounds for appeal include: the trial judge allowed the prosecutor to use illegally obtained evidence; the trial judge ruled incorrectly on objections made by a defense attorney at a trial or at the sentencing hearing; the defendant was not properly advised of their rights during certain phases of the case.