Canon 1501. A judge cannot investigate any case unless a plea, drawn up in accordance with canon law, is submitted either by a person whose interest is involved, or by the promotor of justice.

Iudex nullam causam cognoscere potest, nisi petitio, ad normam canonum, proposita sit ab eo cuius interest, vel a promotore iustitiae.

Canon 1502. A person who wishes to sue another must present a petition to a judge who is lawfully competent. In this petition the matter in dispute is to be set out and the intervention of the judge requested.

Qui aliquem convenire vult, debet libellum competenti iudici exhibere, in quo controversiae obiectum proponatur, et ministerium iudicis expostuletur.

Canon 1503. §1 A judge can admit an oral plea whenever the plaintiff is impeded from presenting a petition or when the case can be easily investigated and is of minor significance.

§2 In both cases, however, the judge is to direct a notary to record the matter in writing. This written record is to be read to, and approved by, the plaintiff, and it takes the place of a petition written by the plaintiff as far as all effects of law are concerned.

§1. Petitionem oralem iudex admittere potest, quoties vel actor libellum exhibere impediatur vel causa sit facilis investigationis et minoris momenti.

§2. In utroque tamen casu iudex notarium iubeat scriptis actum redigere qui actori legendus est et ab eo probandus, quique locum tenet libelli ab actore scripti ad omnes iuris effectus.

Canon 1504. The petition by which a suit is introduced must:

1° state the judge before whom the case is being introduced, what is being sought and from whom it is being sought;

2° indicate on what right the plaintiff bases the case and, at least in general terms, the facts and evidence to be submitted in support of the allegations made;

3° be signed by the plaintiff or the plaintiff’s procurator, and bear the day, the month and the year, as well as the address at which the plaintiff or the procurator resides, or at which they say they reside for the purpose of receiving the acts;

4° indicate the domicile or quasi-domicile of the respondent.

Libellus, quo lis introducitur, debet:

1° exprimere coram quo iudice causa introducatur, quid petatur et a quo petatur;

2° indicare quo iure innitatur actor et generatim saltem quibus factis et probationibus ad evincenda ea quae asseruntur;

3° subscribi ab actore vel eius procuratore, appositis die, mense et anno, necnon loco in quo actor vel eius procurator habitant, aut residere se dixerint actorum recipiendorum gratia;

4° indicare domicilium vel quasi-domicilium partis conventae.

Canon 1505. §1 Once he has satisfied himself that the matter is within his competence and the plaintiff has the right to stand before the court, the sole judge, or the presiding judge of a collegiate tribunal, must as soon as possible by his decree either admit or reject the petition.

§2 A petition can be rejected only if:

1° the judge or the tribunal is not legally competent;

2° it is established beyond doubt that the plaintiff lacks the right to stand before the court;

3° the provisions of can. 1504 nn. 1-3 have not been observed

4° it is certainly clear from the petition that the plea lacks any foundation, and that there is no possibility that a foundation will emerge from a process.

§3 If a petition has been rejected by reason of defects which can be corrected, the plaintiff can draw up a new petition correctly and present it again to the same judge.

§4 A party is always entitled, within ten canonical days, to have recourse, based upon stated reasons, against the rejection of a petition. This recourse is to be made either to the tribunal of appeal or, if the petition was rejected by the presiding judge, to the collegiate tribunal. A question of rejection is to be determined with maximum expedition.

§1. Iudex unicus vel tribunalis collegialis praeses, postquam viderint et rem esse suae competentiae et actori legitimam personam standi in iudicio non deesse, debent suo decreto quam primum libellum aut admittere aut reicere.

§2. Libellus reici potest tantum:

1° si iudex vel tribunal incompetens sit;

2° si sine dubio constet actori legitimam deesse personam standi in iudicio;

3° si non servata sint praescripta can. 1504, nn. 1-3;

4° si certo pateat ex ipso libello petitionem quolibet carere fundamento, neque fieri posse, ut aliquod ex processu fundamentum appareat.

§3. Si libellus reiectus fuerit ob vitia quae emendari possunt, actor novum libellum rite confectum potest eidem iudici denuo exhibere.

§4. Adversus libelli reiectionem integrum semper est parti intra tempus utile decem dierum recursum rationibus suffultum interponere vel ad tribunal appellationis vel ad collegium, si libellus reiectus fuerit a praeside; quaestio autem reiectionis expeditissime definienda est.

Canon 1506. If within a month of the presentation of a petition, the judge has not issued a decree admitting or rejecting it in accordance with can. 1505, the interested party can insist that the judge perform his duty. If, notwithstanding this, the judge does not respond within ten days of the party’s request, the petition is to be taken as having been admitted.

Si iudex intra mensem ab exhibito libello decretum non ediderit, quo libellum admittit vel reicit ad normam can. 1505, pars, cuius interest, instare potest ut iudex suo munere fungatur; quod si nihilominus iudex sileat, inutiliter lapsis decem diebus a facta instantia, libellus pro admisso habeatur.