The determination of whether a patient has criminal responsibility or is able to stand trial is routine psychiatric work. Cases in which we- psychiatrists- are asked to express our opinion on whether a patient can testify, however, are quite rare. We shall attempt to clarify some of the issues relating to the testimony of mentally ill patients through a case presentation. In this case, the Court agreed to consider our patient's testimony, only after receiving our expert opinion. We find that the Court's reversal of its original decision and its willingness to consider the testimony of a mental patient in the same trial in which he was initially found unable to stand trial, marks an important precedent. The question of the credibility of the mental patient as a witness has significance beyond this case concerning mental patients' rights in regard to the judicial system. We believe there is a need for further discussion between psychiatrists andjurists regarding the fitness of the mental patient to testify as a witness.