FORUM. - The Latin term forum or forus originally denoted the place or outer space of the house, or even the vestibule that surrounded tombs. Subsequently it designated the place where the market was held, which could also be a private place in the fields or on the streets; thus the centers of the city, or those situated along the great roads of communication, were called fora, where the inhabitants gathered for both private and public business (that is, to hold market, to hold assemblies or elections, to have communication of the laws, to celebrate ceremonies, to seek and obtain the administration of justice). This latter meaning then became prevalent, and forum designated without further qualification the place where judicial disputes are settled, that is, the place where jurisdiction is exercised or even the ambit of that jurisdiction, hence also the competent tribunal, and finally even the jurisdiction itself (cf. Paul the Deacon [ed. C.O. Müller, Leipzig 1839], p. 84, 9). To preserve, however, for the word forum a proper sense distinct from jurisdiction, it is well to say that the forum is the sphere or ambit in which jurisdiction is contained and exercised, that is, the place, the seat, the authority competent to settle a determined kind of dispute or to regulate a determined kind of business. In this way the forum is distinguished also from competence: the former is, as has been said, the place, understood not only materially but also formally, of jurisdiction; competence, on the other hand, is the part of jurisdiction assigned to a determined organ or person.
Both the Church and the State are invested with the power of jurisdiction or governance; this power, however, is contained within a determined ambit, to which the name forum is given; there is therefore the ecclesiastical forum and the civil forum.
It belongs exclusively to the ecclesiastical forum to judge: 1) cases that concern spiritual things or things annexed to spiritual things; 2) the violation of ecclesiastical laws and the determination of the sinful character of an act, in relation to the definition of guilt and the imposition of ecclesiastical penalties; 3) all contentious or criminal cases concerning persons who enjoy the privilege of the forum according to canon law (can. 1553 § 1). In cases said to be of mixed forum, that is, of common competence of the Church and the State, the criterion of prevention applies, that is, the authority, ecclesiastical or civil, that was first invested with the case judges it (can. 1553 § 2).
In Italy, with the Lateran Pacts, full juridical efficacy, also for all civil effects, was recognized for the sentences and measures issued by ecclesiastical authorities and officially communicated to the civil authorities, concerning ecclesiastical or religious persons and concerning spiritual or disciplinary matters (Treaty, art. 23; Concordat, arts. 5 and 20). It is further recognized that cases concerning the nullity of marriage and the dispensation from a marriage ratified and not consummated are reserved to the competence of ecclesiastical tribunals and dicasteries. As for cases of personal separation, the Holy See consents that they be judged by civil tribunals (Concordat, art. 34; law of 27 May 1949, no. 847).
While in civil law forum commonly means the tribunal or the judicial function, in canon law the word forum instead preserves its broader sense, as given above. There is therefore, according to the diversity of the ends it pursues, of the sphere in which it operates and of the manner in which it is exercised, a jurisdiction of the external forum and a jurisdiction of the internal forum (the external forum is also called forum fori, because in it actions are considered under their public or social aspect; the internal forum, or forum of conscience, is also called forum poli because it concerns the eternal salvation of individual faithful, and eternal salvation is like the pole of souls). The jurisdiction of the external forum is directed directly to promoting and defending the public good, that is, of the community of the faithful, and to regulating their social activity; the jurisdiction of the internal forum, on the other hand, aims directly at the spiritual good of individuals and therefore concerns their private actions, insofar as they relate to their conscience and to eternal life.
This distinction does not exist in civil law, because the civil authority always exercises its power for the good of society, and only indirectly for private good. This double power, on the other hand, is in the Church a consequence deriving from its very nature. It is in fact a spiritual and supernatural society, constituted for the salvation of men, and men, in order to attain salvation, need not only an authority that directs them all together and socially, but also a direction of individuals, according to the particular conditions and circumstances of each. Civil society finds the family already constituted by nature, which provides directly, in the natural order, for the good of individuals; the Church, on the other hand, a supernatural society, does not find constituted in this order any society or organ that takes care of individuals; consequently it falls to it to take direct care of these as well.
The jurisdiction of the external forum is exercised publicly and has juridical effects, while the jurisdiction of the internal forum is exercised privately and has, of itself, no public effect.
Since the jurisdiction of the external forum concerns the exterior relations of subjects with society and has as its end the common good, it can be said, and is truly, also in the Church, a properly human power; the power of the internal forum, on the other hand, which concerns the relations of souls with God and has as its end the salvation and sanctification of souls, which is a divine work, is an essentially divine power. It follows that the former is a power proper to the Church, and it is its principal agent; the latter, on the other hand, is exercised by the Church as vicar of God: the principal agent in its exercise is in fact God himself, whose place the Church, or its ministers, take, and only in the case in which it concerns positive ecclesiastical law is the power of the internal forum also proper to the Church. Both are of divine institution. The power of jurisdiction in the external forum does not formally concern divine law as such, but everything that is directed to the social end of the Church; nevertheless, since for this end it can be useful to command or prohibit even what is already imposed or forbidden by divine law, what was previously obligatory only before God can be made obligatory also in the external forum and before the ecclesiastical society. It follows that the jurisdiction of the external forum is principally directed ad ligandum, whether by extending to the ecclesiastical forum precepts or prohibitions that were previously only of the divine forum, or by promulgating laws or issuing orders by virtue of the power committed to ecclesiastical authority. Since, however, ecclesiastical laws oblige also in conscience, what binds in the forum of the Church binds also before God. The power of the internal forum, on the other hand, formally concerns divine law, understanding by this not only the norms established directly by God, but also the obligations that positive human laws produce in conscience. The power of the internal forum is therefore principally ordered ad solvendum, not divine law but the obligation that, through human action, has been contracted before God: by sin, by oath, by vow, etc., or the obligation that has arisen from ecclesiastical law before God (cf. L. Billot, Tractatus de Ecclesia Christi, 3rd ed., I, Rome 1809, pp. 456-66). The same precepts that can be imposed in the internal forum, such as, for example, sacramental Penance, the work into which a vow is commuted, etc., are directed to the dissolution of the bond contracted in the divine forum.
The jurisdiction of the external forum differs, as has been said, from that of the internal forum as public good differs from private good. However, given that the public good public good cannot be conceived without the good of individuals, and the good of individuals cannot prescind from the common good, it is not always easy to distinguish what pertains to the one or the other. The difficulty is even more serious in the Church, where it happens that the good of a single soul concerns the whole society. It may be said, moreover, that the following belong to the internal forum: a) all actions insofar as they are considered under the aspect of sin, and therefore also crimes, not insofar as they disturb society, but insofar as they disturb the conscience; b) all hidden actions, as long as they remain hidden (when they become public they pass to the external forum if by their nature they belong to it); c) the faculties directed to the good of individual souls: thus the faculty of preaching tends directly to persuade each individual of the Catholic truth; the faculty of absolving tends to the forgiveness of the sins of individuals. The following belong to the external forum: a) the legislative, judicial and executive power; b) the power to grant the faculty of preaching and of absolving, etc., because it is directly of public utility that ministers be designated who preach, absolve, etc. As the object is different, so too in the one and the other forum the manner of proceeding is different: in the internal forum one proceeds secretly and coram Deo, in the external forum publicly and coram Ecclesia. Given the distinction existing between public and private utility and between the one and the other forum, there can be subjects invested with power in the internal forum without jurisdiction in the external forum, as, for example, parish priests; and conversely there can be subjects invested with jurisdiction in the external forum without power in the internal forum. According to canon 202 § 3, however, unless it is established otherwise, jurisdiction is understood to be granted for both forums. Ecclesiastical jurisdiction, in fact, by its nature pervades both the one and the other forum, but the will of the grantor or the very nature of the grant can restrict its scope to one alone: thus, for example, the power to absolve can be limited to the internal forum; the power to judge limits jurisdiction to the external forum. An act performed by virtue of the power of jurisdiction (whether ordinary or delegated is of no importance) in the external forum has full effect also for the internal forum (can. 202 § 1); on the other hand, an act of jurisdiction granted only for the internal forum has effect only for the latter. If therefore a matter defined in the internal forum alone passes to the external forum, an act of jurisdiction is required to define it also in this forum, unless the law itself provides otherwise (cf., for example, can. 1047).
Although the external forum and the internal forum are generally in agreement, there can nevertheless be cases of conflict, when the possibility of proof in the external forum is lacking (for example, a marriage can be null for lack of consent, but proof of such lack may be wanting; cf. also can. 2251). In case of conflict the external forum prevails, provided that observance of it is possible without fault before God; otherwise the internal forum prevails, because divine law prevails over human law.
The external forum can be distinguished into judicial and extrajudicial, according to whether jurisdiction is exercised or not in the form of a judgment. The judicial forum can in turn be subdivided into contentious or criminal: the contentious concerns the definition of disputed rights or the declaration of the juridical facts of natural or juridical persons, while the criminal has as its object crimes in relation to punishment (can. 1552 § 2). The procedural norms are for the most part common to both judgments, and the ecclesiastical judicial organs have civil and criminal competence.
The power of the internal forum in turn is subdivided into sacramental (anciently also called penitential) and extra-sacramental: the first can be exercised only in the sacrament of Penance or on the occasion of it: thus it happens, by divine law, for the remission of sins, and by ecclesiastical law in the cases in which the power to dispense or to absolve from penalty in the act of confession is delegated to confessors (cf. cann. 1044, 2250 § 3, 2254, 2290); the second extends to all acts which, while remaining within the scope of the internal forum, can be performed outside the sacrament of Confession: such as dispensations from vows, from irregularities and from hidden censures, etc.