APOSTLES. – In medieval canon law procedure, this term referred to the letters that a lower judge was required to transmit, within a specified time, to the appellate judge, to inform him of the appeal having been lodged and of the merits of the case (cf. c. 39, X, II, 28; c. 1, II, 12 in Clem.; etc.). The name, however, like the institution itself, derived from Roman law: cf. D. 49, 1, 1; 50, 16, 106; etc.
Various kinds of apostles were distinguished: dimissorii, delatorii, reverentiales, refutatorii, testimoniales, conventionales, repositorii, depending on the different weight attributed to the appeal.
The institution, if not the name, remained in force, albeit somewhat mitigated, until recent times. The Code of Canon Law makes no mention of apostles, but in a way incorporates their substance into the institution of prosecutio appellationis (canons 1833 ff.), even aligning itself with the stricter Roman discipline, albeit in a simplified form (see APPEAL).