Canon 1678. §1 In cases of the nullity of marriage, a judicial confession and the declarations of the parties, possibly supported by witnesses to the credibility of the parties, can have the force of full proof, to be evaluated by the judge after he has considered all the indications and supporting factors, unless other elements are present which weaken them.

§2 In the same cases, the testimony of one witness can produce full proof if it concerns a qualified witness making a deposition concerning matters done ex officio, or unless the circumstances of things and persons suggest it.

§3 In cases of impotence or defect of consent because of mental illness or an anomaly of a psychic nature, the judge is to use the services of one or more experts unless it is clear from the circumstances that it would be useless to do so; in other cases the prescript of can. 1574 is to be observed.

§4 Whenever, during the instruction of a case, a very probable doubt arises as to whether the marriage was ever consummated, the tribunal, having heard both parties, can suspend the case of nullity, complete the instruction for a dispensation super rato, and then transmit the acts to the Apostolic See together with a petition for a dispensation from either one or both of the spouses and the votum of the tribunal and the bishop.

Canon 1679. The sentence that first declared the nullity of the marriage, once the terms as determined by can. 1630-1633 have passed, becomes executive.

Canon 1680. §1 The party who considers himself or herself aggrieved, as well as the promoter of justice and the defender of the bond, have the right to introduce a complaint of nullity of the judgment or appeal against the sentence, according to can. 1619-1640.

§2 After the time limits established by law for the appeal and its prosecution have passed, and after the judicial acts have been received by the tribunal of higher instance, a college of judges is established, the defender of the bond is designated, and the parties are admonished to put forth their observations within the prescribed time limit; after this time period has passed, if the appeal clearly appears merely dilatory, the collegiate tribunal confirms the sentence of the prior instance by decree.

§3 If an appeal is admitted, the tribunal must proceed in the same manner as the first instance with the appropriate adjustments.

§4 If a new ground of nullity of the marriage is alleged at the appellate level, the tribunal can admit it and judge it as if in first instance.