Lately, within the penal lawsuit – in the stage of its prosecution and judgment – due to the impasse of producing evidence facing the prosecution, since the prosecutor issues solutions for not initiating the penal prosecution without factual or legal grounds, with regard to the delator that perpetrated deeds provided by the penal law and closely connected with the crimes for which they ordered the judgment of others, they heard and then obtained that such delators be heard as witnesses and grounded its accusation on their testimonies. The clarification of the capacity in which a delator may be heard within a penal lawsuit appears, therefore, necessary both from a theoretical point of view, and from a practical point of view, and the authors’ approach is trying to respond to this necessity.