§ 1. The highest right is sometimes the highest wrong, and this arises from a rigid interpretation of laws. What they call equity, or ἐπιείκειαν, remedies this. It then corrects a law when, in a singular deed which the legislator could not foresee but which, had he foreseen it, he would expressly have excepted, the law is judged not to oblige. Thus St. Thomas, Summa theologiae I–II, question 96, article 2.
§ 2. The interpretation of equity arises from a defect of a law which speaks universally; therefore it has no place either in natural law or in positive divine law, since their legislator foresaw all things. When this equity is evident, it is lawful for anyone; when doubtful, it must be determined by the superior.
§ 3. For a law to be judged not to oblige on grounds of equity, it is not a sufficient reason that the cause of the law ceases. It ceases in a particular case only when the law errs because of its universality, so that it would be either inequitable or harmful if it were observed. For example, let the law be: “Let no one ascend the wall; if anyone ascends it, let it be a capital offense.” Gaius ascends the wall in order to repel the enemy. Who would doubt that Gaius is unjustly summoned as guilty of violating the law? But the legitimate reason must be of such a kind. For although the reason ceases negatively in the particular case, if it remains in common the will of the legislator can will to oblige the person in whom it ceases in the particular case.
Otherwise a great dissolution would arise in the state, and many laws would be violated without fraud. It is therefore necessary that the reason of the law cease in the particular case in such a way that the law would be unjust or very burdensome in that particular case. The matter is manifest from an example. The cause why ascending the wall is a capital offense is that an enemy or traitor may not seek an opportunity to destroy the city. Gaius is an excellent man, most loving toward his fatherland, and exceedingly rich; his safety depends upon the safety of his fatherland. There is therefore no danger that, by ascending the wall, he himself will create danger for his fatherland. The cause of the law therefore ceases in his case. Yet because it remains in common, and the legislator rightly comprehends even the best citizens under that law so that he may cut off the opportunity from the wicked, Gaius will be bound by that law. For if he ascends, many will follow who will also assert that they are most loving toward their fatherland, and thus it will be conceded to every most wicked person.
Next, it is necessary that it be the adequate reason of the law which ceases. Guardianship is entrusted to the nearest agnates, law 1, On Legitimate Guardianship, π. The reason of the law is that the law believed that goods could be administered no more safely and preserved no better than by the person who hopes that the same goods will at some time come to himself and his own. And thereafter, because it is equitable that the person who hopes for the profit should also undertake the burdens; a closer affection and friendship is added. It can happen that the reason of the law ceases, if it were known that the agnate would administer neither better nor more safely, and would not love the wards more; indeed, ordinarily a neighbor or some other person is more friendly than kindred. Nevertheless, the agnate is not to be repelled from the guardianship unless it is established that he would administer badly and had been hostile to the agnate.
The law of Solon was contrary to this: Τῶν ὀρφανῶν κληρονόμον ἐπίτροπον μὴ εἶναι. “Let the heir of orphans not be their guardian.” The reason was that he judged it dangerous for the ward to be in the power of one to whom his death would be profitable. That law had to be maintained at Athens although the ward’s heir was a man of the greatest integrity, from whom there was no danger. But if that heir were childless and rich, and had instituted the ward as his heir; if the ward had lawsuits which he would most willingly and ably prosecute; and if the ward would suffer great loss through lacking him as guardian—then the law would be abrogated through equity. Otherwise, if the reason is not grave, it is always expedient that particulars accommodate themselves to common rules.
§ 4. When a human law concerns indifferent matters, upon the cessation of its adequate cause, whether negatively or contrarily, the law itself altogether ceases. Thus, if there is a law for contributing taxes to build a bridge, once it has been completed the law of the tax ceases; indeed, it is unjust. For when its cause ceases, the law is useless to the state, and the state is not to be burdened by laws which contribute nothing to the public good.
§ 5. For this reason very many laws of the ancients were abolished by Justinian’s jurists, as the emperor acknowledges in the prefaces, and so was a great part of the laws of the Pandects and the Codes which has now been amended by other laws.
§ 6. If a human law prescribes a law which commands some act of virtue, it will retain its force even when the cause ceases. For there is sufficient cause in the exercise of virtue itself for the law to have been carried, provided that it is not excessively burdensome. For that act is capable of law of itself and by its nature; therefore the obligation remains until it is taken away by the prince. An example is that it was ordained that at first, against the Arians, there should be sung in the churches: “Glory to the Father, and to the Son, and to the Holy Spirit.” Because that act is good and religious by its nature, that law remains although in many places not even the name of the Arians survives.
§ 7. Dispensation in a human law occurs when, while
the law and its cause remain, the obligation is removed from one, another, or several persons.
There was a law which guarded Roman liberty, that in the administration of provinces there should be annual succession. Released from the law, Caesar governed the Gauls for ten years. From another quarter it was arranged that Pompey should be released from the laws. They properly call it dispensation when someone is released from a law for a time; otherwise, when he is perpetually free from a law, it is called exemption. When it is converted into another obligation, it is called commutation of the law.
§ 8. A prince, whether ecclesiastical or secular, can dispense from his own laws and those of his predecessors. For since it is in their power to oblige, it will also be in their power to remove an obligation, and to do so from this or that person as reason dictates. Next, an inferior magistrate can dispense from the law of a superior with the tacit or express consent of the superior, or by custom. Indeed, if the matter is of small importance and frequent, he can do so without approaching the superior.
§ 9. For a dispensation to be legitimate, it is necessary that its cause be legitimate. For it is contrary to the common good that some be released from laws without any cause, since all ought to conform themselves to the community. Next, the prince is bound by his own laws; if he can dispense without cause, he will never be bound by them. Therefore, a prince sins by dispensing without cause. Next, one who uses the dispensation commits an offense against the natural law which commands that a part be conformed to the whole state. Nevertheless, the thing itself which is conceded is valid. But if the cause of the dispensation was just, when it ceases the dispensation also ceases; when the cause returns, the dispensation returns.
But if the law has simply been removed, although the cause ceases before execution, the person can use that removal. Thus, if someone has been dispensed from an irregularity because of a scarcity of priests, even if the scarcity ceases before he has received orders, the dispensation nevertheless remains, because the irregularity has been altogether removed.