rescripts obtained by obreption or subreption are null and void when the motive cause of the rescript is affected by them if it is only the impelling cause and the substance of the petition is not affected or if the false statement was made through ignorance the rescript is not vitiated as requests for rescripts must come through a person in ecclesiastical authority it is his duty to inform himself of the truth or falsity of the causes alleged in the petitions and in case they are granted to see that the conditions of the rescript are fulfilled