A motion for new trial asks to overturn or set aside a court's decision or jury verdict. Such a motion is proposed by a party who is dissatisfied with the end result of a case. This motion must be based on some vital error in the court's handling of the trial, such as the admission or exclusion of key evidence, or an incorrect instruction to the jury. Generally the motion is filed within a short time after the trial (7–30 days) and is decided prior to the lodging of an appeal. In some jurisdictions, a motion for new trial which is not ruled upon by a set period of time automatically is deemed to be denied.