Summa Theologiae Moralis, vol. I: De Principiis

On the Fulfillment and Interpretation of Human Law.

S. Th. I-II, q. 96, a. 6 ; 97, a. 3, ad 2 ; II-II, q. 60, a. 5, ad 2 ; q. 120.

293. How law is to be fulfilled. — The human legislator directly does not prescribe the internal manner of virtue, but the preservation of social order ; whence he prescribes only the substance of the prescribed act and is content with the physical or external fulfillment, although he may intend the good of virtue. For the end of the precept does not fall under the precept ; nor therefore of itself the manner (extrinsic) of fulfilling the precept, unless the manner be of the substance of the precept (intrinsic). These things will be more fully explained, where ecclesiastical law is treated.

294. How law is to be interpreted. — But in order that it be rightly fulfilled as is fitting, the law often needs interpretation. For human law cannot be so perfectly expounded as to exclude every doubt about its sense, and therefore it often needs interpretation, either because of the weakness of human intellect, or because of the change of circumstances and customs.

Interpretation is the clearer determination of the mind or words of the legislator. Which by reason of value or efficacy is twofold : authoritative which is imposed with authority, and merely directive which can also be made by private persons. By reason however of cause or author it is fourfold :

1° Authentic or legal which is made authoritatively by the very ruler of the community as such, who is deservedly considered better to know the sense of the law and therefore enjoys the authority of interpreting : it is made by the legislator himself, or his successor or superior, or also by another specially designated for this (as is done in France by the Council of State), and has the same force as the law itself.

In our country art. 28 of the Belgian Constitution holds : « The interpretation of laws by way of authority belongs only to the legislative power. »

2° Usual which is made by the general observance of the community, or by the use and custom of the people, which therefore is called the best interpreter of laws. Moreover custom is either antecedent to the law, and this can avail for apprehending the sense of the law which according to custom is wont to be enacted ; — or concomitant is the manner of observing the law, and this avails as a sign and witness for discerning the mind of the legislator, because it exhibits the common sense of the subjects, which, although it is not authentic, nevertheless avails more than doctrinal interpretation because many agree in it ; — or subsequent which, given the conditions, can define or extend a pre-existing obligation just as it can introduce or remove it (as we have said n. 273) : then it is authoritative. In present-day civil law however the force of custom is not admitted for interpreting authoritative law, neither for introducing it nor for abrogating it.

3° Judicial which is made authoritatively by the judiciary power in order for a special case, namely applying the law to a particular fact : it is authoritative as to the litigants ; as to others it has only the private authority of the judge, so much the greater as he is possessed of greater knowledge and the interpretation is more often repeated, however greater other things being equal than if it were given by a private doctor.

4° Doctrinal which is not authoritative and therefore of itself not obligatory, but based on and directed by knowledge, and is made by private doctors or jurists according to the rules of the critical art. It is so much the greater as their number and excellence, and the arguments, are greater ; if all agree in the interpretation, it would be rash to despise it.

295. How manyfold interpretation is. — By reason of its nature or manner in which it is made, interpretation is simply declarative or comprehensive, which uniquely declares the words and sense of the law and adds or removes nothing, whether they declare more or less clearly, or even elucidate obscurities ; this can be made by all, even private persons ; — or supplementary which adds what is lacking to the sense and words of the law, and is either extensive, which adds an obligation previously not expressed or intended, and therefore needs promulgation, or restrictive, which alters and removes : this, just as the law itself, can be made by the authority of the legislator, and by custom, provided the consent of the legislator can be presumed.

296. Interpretation by epikeia. — Even the subject of the law can, in rare particular cases, make a certain quasi restrictive interpretation and licitly act contrary to the words of the law, when namely this would be harmful to the common good. For a law obliges only insofar as it ordinarily [leads] to the common good, and does not oblige if it falls short of this. It happens however that something is useful generally and in many cases, and in certain cases is harmful ; but because the legislator cannot foresee all cases (nor can the law enumerate all cases because it would become more obscure), the law is proposed according to what happens in many cases for the sake of the common good.

Therefore in the case where the observance of the law would be harmful to the common good, it is not to be observed ; for the legislator is rightly considered not to have wished to comprehend that case in the law, just as the law about closing the gates of a town would not be applied to a citizen who was very useful for defending the city, and the law which forbids carrying arms does not oblige him who is sought by an enemy for death.

The right judgment about the circumstances in which the law does not oblige, and the moral virtue inclining (under the direction of prudence) to right acting according to such a prudent judgment (which pertains to legal justice) is called epikeia (ἐπιείκεια i.e. equity, benignity, moderation), which interprets and judges and applies the laws according to what is equitable and good, i.e. according to what the reason of justice and common utility demands. « In theological use it designates a certain explanation of the law which is made from equity, a benign interpretation prudently moderating the law beyond the rigor of the words, by which it is judged that the law does not extend to some particular case, because of its special circumstances, although the words of the legislator, as they sound, contain even this case¹ ». It can be defined as : an equitable and benign interpretation of the law, or a prudent moderation and restriction, by which contrary to the words or sense of the law we follow the habitual mind of the legislator.

It is twofold : one in the broad sense does not exceed the limits of simple interpretation drawn from the circumstances, and has place not only in positive but also in natural law (e.g. deposits are to be returned) ; the other in the strict sense contains an emendation of the law and has place in human law alone. And the latter differs : a) from simple interpretation, which explains obscure words and inquires whether in this or that sense these words are to be taken, so that they comprise these or those cases : this follows the literal sense of the law and the mind which the legislator had, that departs from the words and the clear literal sense of the law and follows the mind which the legislator would have had, or reasonably ought to have had if he had foreseen the case ; — b) from a simple cessation of the end : for by this the law ceases in universal and indeed negatively or contradictorily because its end is lacking, but by epikeia it does not oblige in a particular case and indeed contrarily because the law is rendered harmful or too burdensome ; — c) from dispensation : for this is an act of jurisdiction by which the legislator looses the bond of the law in a special case to which otherwise the law would have to be applied ; but epikeia declares that such a case was never comprised in the law, although it is comprised in the words.

297. Epikeia in the strict sense has place whenever the law is 1) harmful or evil, e.g. if it cannot be observed without sin ; or 2) so much an impediment to good or very burdensome and too difficult that it can scarcely be imposed by an equitable legislator ; or 3) not sufficiently burdensome and difficult that it cannot be imposed, but nevertheless, the circumstances being considered and especially the ordinary manner of prescribing with moderation, it is presumed that such was not the mind of the legislator. But ordinarily it does not occur in laws which render invalid because of the common good.

The interpretation of epikeia can be made by any private person if the cause is evident ; — if it is doubtful, the superior must be approached, because it pertains to him to interpret what is useful or useless for the community, whence for such cases he has the power of dispensing : for it is disorderly to pass over the words of the law where the will of the legislator can be known with certainty, and in doubt about the lawfulness of the act, we must, as far as we morally can, arrive at certainty (n. 213 and 214, 4°) ; — but if it is a cause which does not admit of delay in having recourse to the superior and is sufficiently founded (so that there is positive doubt that the law still obliges), the very necessity dispenses, which has no law : for then it suffices that the law has probably ceased to oblige.

By present-day civil law however epikeia is equally admitted, except in the case where it would evidently harm directly the common good — namely, the legislator restricts it to the least possible, and judges it better to observe the law, even if it be burdensome to one or another, for the sake of the example to others.