This summary is not the rule. The rule text controls.
If someone has been found guilty or has pleaded guilty or no contest, this rule lets them ask the court to cancel that judgment under certain limited conditions. The court must cancel the judgment if the original charge never actually described a real crime, or if the court never had the legal authority to handle that type of case in the first place.
To make this request, the defendant has to file it within 10 days after the guilty verdict, guilty finding, or plea. The court can allow more time, but only if it grants that extra time within the original 10-day window. Waiting too long without the court's permission means losing the chance to make this request.
This rule is not about arguing that the evidence was weak or that a mistake happened during the trial. It only applies to two specific problems: the charge itself was legally invalid, or the court had no power to judge that particular offense. If either of those problems exists, the case cannot move forward with a valid conviction.