Oral testimony is not required in:-Dying declaration. Deposition of medical witness taken in lower court. Evidence given by a witness in a previous judicial proceedings. Expert opinion expressed in a treatise (ex. book). Report of a certain government scientific experts eg. chemical examiner, assistant chemical examiner, chief inspector of explosive, director of finger print bureau. Statement by persons who cannot be called as witness (the person is either dead, untraceable or has become incapable of giving evidence or cannot be called without unreasonable delay or expense to the court).