Summa Theologiae Moralis, vol. I: De Principiis

S. Th., I-II, q. 97, a. 2.

401. Abrogation (abroger, révoquer, rapporter) is the abolition or revocation of the whole law ; derogation (déroger, modifier) is the abolition or revocation of a part of the law, the other retaining its force. They differ from invalidation of law : this is the abolition by a superior of a law enacted by an inferior so that it never obtains force ; those however revoke a law which had force.

They can be done directly or expressly (formal cessation), or tacitly and indirectly (virtual cessation) by enacting an incompatible law (abrogation).

402. Those who can enact laws can abrogate and derogate, namely the legislator himself, his successor and superior. For « every thing, by whatever causes it is born, by the same is dissolved ».

As to ecclesiastical laws : the Pontiff for all ; — Councils for the laws of their territory ; — bishops for diocesan [laws] even those enacted in synod, not however for laws enacted in a provincial council, or for diocesan [laws] if they have been confirmed by the Roman Pontiff in specific form, i.e. not simply in favor of the superior, but in favor of the community, so that the Pontiff has made them his own.

They will do this validly even without reason, because positive law essentially depends on the will of the legislator ; they will not do it licitly without a just cause, because it brings detriment to the common good to abrogate useful laws or frequently to change them into others : for thus the people are despised, and the laws are less esteemed and observed, whereas for the observance of law custom avails much.

403. Remarks. — 1. Note can. 22 : « A later law, enacted by competent authority, abrogates a prior one, if it expressly so declares, or is directly contrary to it, or entirely reorders the whole matter of the prior law ; but a general law in no way derogates from the statutes of particular places and singular persons, unless something else is expressly provided in it ». However, from the express determination of law, « whatever laws, whether universal or even particular, opposed to the preceptive [parts] of the Code, are abrogated, unless about particular laws the contrary is expressly established » (can. 6, 1°).

2. About tacit abrogation note : a) that a later law is to be reconciled with an earlier one, insofar as the propriety of words permits (can. 23), for the change of law is in itself harmful to the community and to be strictly interpreted ;

b) by a general law a prior general law is abrogated insofar as it is directly contrary ; not particular customs or statutes of particular places or of singular persons, which can be unknown to the legislator ;

c) by a later general law a prior general law is abrogated, not only the contrary but also the diverse one, if the later entirely reorders the matter of the prior law (can. 22). For it is contrary to the common good that the same argument be subject to a twofold ordering.