A new trial may be granted on any of the following grounds:(a) When material evidence is discovered which, despite reasonable diligence, could not be discovered or produced at the trial.(b) When it is impossible to prepare a narrative statement of the evidence or when a transcript of the stenographic notes of the proceedings cannot be obtained because of the death or disability of the stenographer, or because of the absence or loss of the corresponding tape.(c) When substantial justice requires it, the court may grant a new trial to all or any of the parties and on all or part of the issues.
Puerto Rico Legal Code