Chapter IV. On Unwritten Law, or Custom

137. • Custom, insofar as it is considered causally, is a mode of acting induced from frequent acts of the whole community, or of the greater part of the same; but formally it is a certain right constituted by morals, which is accepted as law, even if law is lacking.

Principles. - I. Custom, clothed with due conditions, can introduce a new law, abrogate an old one either wholly or in part, for example as to the penalty while the obligation remains, or conversely, and likewise modify or interpret a law. This is established from various places of both Canon and Roman Law, from which it is indubitably drawn that custom is to be held as law. It is likewise established from the common opinion of theologians and legal experts. Hence the axiom: Custom is the best interpreter of laws.

II. The conditions for introducing or abrogating a law are 1. That the custom be reasonable. For this it is required that it not break the nerve of ecclesiastical discipline; furthermore, that it not be a tinder and occasion of sins, nor pernicious to the common good. Bouix. - 2. That it be introduced by a community (and indeed by the greater part of the same, capable of establishing a law, Bouix), through repeated acts (and not interrupted up to the completed custom, Reiffenstuel), voluntary acts (that is, not introduced by force or fear ¹, Bouix), public acts, with at least an implicit intention of obliging themselves (if it is a matter of custom beyond the law). - 3. That it endure for the required time.

¹ Add that the acts ought not proceed from error or ignorance. For otherwise, since nothing is more contrary to consent than error, the acts would be judged involuntary.

For attributing the force of law to custom, the express consent of the Prince is not required, but legal or juridical consent suffices, which is had through the laws and canons approving custom introduced by the morals of the people, and attributing to it the force of unwritten right.

138. Questions. - QUESTION 1. What time is required for prescribing against a law?

I answer: It is controverted; nor do Theologians or legal experts agree among themselves, because the laws establish nothing clearly concerning this matter.

Most say that ten years suffice and are required for prescribing against a civil law ². Many affirm the same also for ecclesiastical law, although certain others, with Billuart, require 40 years. - Thus St. Lig., no. 107; Apostolic Man, no. 11. - But this seems to depend not so much on length of time as on the other circumstances considered by moral estimation, having regard especially to the common sense, namely whether the greater and sounder part of the community holds the law as abrogated ³.

² Namely, for this a long time is required and suffices. But the laws hold ten years as a long time. Institutes, On usucaption, beginning, and Law 12, Code, On prescription of long time.

³ In this case the law can cease before ten years, not indeed by force of custom, which by hypothesis has not yet prescribed; but from the consent of the Prince conniving, and thus tacitly taking it away.

139. • QUESTION 2. When is custom judged to have been introduced with the intention of obliging oneself?

I answer: 1. If the Doctors agree in this; 2. if the custom is about a grave and difficult matter, and nevertheless can be said to have been observed constantly and commonly; 3. if Superiors gravely rebuke violators of customs. - St. Lig., no. 107.

QUESTION 3. What is to be held in doubt whether a custom has the force of law?

I answer: In doubt, after inquiry has been made, the principle holds: A doubtful law does not oblige. But this inquiry consists in investigating the sense of upright men.

140. • QUESTION 4. What is to be held concerning the various ecclesiastical customs proper to France?

I answer: Concerning this matter Bouvier speaks thus in his own words (edition amended according to observations proposed by some Roman theologians), ch. 2, art. 5:

"It is certain that, as regards France, the Supreme Pontiffs do not admit all customs contrary to common law... For although the Supreme Pontiffs have not always been able to protest against these customs, on account of grave inconveniences, whether public or personal, rightly to be feared for themselves or for others, nevertheless it must be believed that by this silence they have not ratified those same customs. Already the Holy See has opened its mind both in particular concerning the obligation of the Bull of St. Pius V concerning the Roman liturgy, and in general concerning pontifical Constitutions regarding general discipline, which it ordered to be admitted by the Council of the Province of Paris of the year 1849, as can be seen in the acts of that same Council.

"It is certain, however, that the mind of the Holy See was not to destroy completely all customs proper to the dioceses of France.

"But which Decrees of common law, or of general Councils, which Apostolic Constitutions have the force of law, and which customs are to be held ratified in the dioceses by consent of the supreme legislator, in doubt recourse must be had to the Holy See. - See case no. 132.

"Many things which regarded benefices, privileges of the external forum, and forms of judgments, are now without object in France. Whence the greatest part of the difficulties of ecclesiastical Law has vanished.

"All Priests can with a safe conscience use customs certainly and without injury to the authority of the Church received among us; indeed in practice they cannot recede from them, because order would be disturbed, for example, if they judged the jurisdiction received from the Bishop insufficient, if they esteemed dispensations conceded as null, etc. It belongs to Bishops, and not to simple Priests, to judge concerning rules of discipline." - Bouvier (edition amended according to observations proposed by Roman theologians), ch. 3, art. 1, § 2.