Institutio Oratoria

At times the character of the accused may be adduced to prove the fact, and to make it likely that it was or was not a case of poisoning because the accused is or is not a likely person to have committed such an act. When, on the other hand, the enquiry concerns both the accused and the act, the natural order for the accuser to pursue is to commence by proving that the act has been committed and then to go on to show that it was committed by the accused. If, however, proofs of the authorship of the crime are more in number than the proofs of the commission, this order may be reversed.

On the other hand, the accused will always begin by denying the act, since if this can be successfully proved, there is no need to say anything more, while if it is not proved, there remain other means of defence. Similarly, when the dispute turns solely on the act and, the act being proved, there can be no doubt as to the author, arguments may be drawn in like manner both from the person and the facts, although with reference to the question of fact alone.