Article III: On Unjust Taking Together with Detention of the Thing

302. A possessor of bad faith is one who culpably detains a thing which he knows belongs to another. Hence by a twofold title he is bound to restitution, insofar as he is the unjust possessor of another's thing, by reason of the thing received, and insofar as he has inflicted damage, by reason of unjust taking. Therefore he must not only restore the thing itself with its fruits, but also compensate all damages following from his unjust action.

303. The general principle is: A possessor of bad faith is bound to restore insofar as he has damaged; whence the measure of restitution is the quantity of damage inflicted. In particular:

A. As to the thing itself: 1) As the unjust possessor of another's thing, he must restore to the owner the thing itself, if he has it, or an equivalent thing, and hence everything in which he has been made richer from it, and as soon as morally possible, unless the owner would be unreasonably unwilling to the delay; because no one ought unjustly to be enriched from another's thing.¹

¹ Nor is recourse given against the seller for recovering the price, because the buyer knew the thing belonged to another (a. 1629).

But if another's thing has successively been possessed by several with bad faith, first of all restitution must be made by him who detains, consumed, or lost the thing; failing him, the robber is bound; and when these fail, the rest are bound according to the rules of restitution in solidum, concerning which in the following article.

2. As an unjust damager, he is bound to repair all detriments which he foresaw at least in confusion would follow from the unjust retention, even if he has been made richer in nothing; because he is the cause of all these.

Hence a) if the thing has been consumed or has perished, even without his fault but by fortuitous chance, he must restore its price, at least if the thing would not certainly have perished with the owner at the same time;

b) if the thing was made worse, while with the owner it would have remained whole, he is bound to compensate the damage;

c) if the owner has undergone some emergent damage, because, for example, he had to buy another thing at a higher price, this also must be repaired.

B. As to fruits, he is bound to restore 1) all fruits (natural, industrial, civil), expenses being deducted, perceived from another's thing, even if the owner would not have perceived them, even if they have been consumed, although from them the possessor did not become richer. For the thing bears fruit for its owner;

2. all fruits which the owner would legitimately have perceived, although the possessor did not perceive them, because he was the unjust cause of this damage; nevertheless this is not to be repaired entirely, but according to the proportion of the probability of the ceasing gain, or of the hope of obtaining it, according to the condition of persons and business affairs (q. 62, a. 4);

3. all fruits perceived by others, if they have not restored them, because he is the cause of this damage by cooperation.

But fruits of the person or of industry alone, which were perceived only on the occasion of the thing, are not to be restored, as being fruits not of the thing but of one's own labor. Thus these need not be restored: hens from the eggs of another, trees taken by theft and planted in one's own field, profit from trading or gambling with deposited money, although one acting thus sinned; but generally it suffices to pay the price of the eggs, of the small trees, of the legal increase, unless, however, further damage was caused.

C. As to expenses, he can deduct 1) necessary and useful expenses (a. 1381); but not pleasurable expenses (a. 1635). But ornaments which can be removed with the substance of the thing preserved and without detriment to it, he can retain for himself.

Thus unless civil law determines otherwise, such as the law in England and in the United States of America, according to which the owner need not refund expenses made by a possessor of bad faith.

304. What if the thing would have perished at the same time with the owner? — Resp.:

1. If the thing certainly would have perished at morally the same time and by the same cause as it perished with the thief, for example, by the same fire, earthquake, shipwreck, incursion of enemies, or from an intrinsic defect of the thing, as a horse from old age, the thief is not bound to restitution of the thing, because he is not the efficacious cause of the damage, nor was the condition of the owner made worse, although nevertheless other damages following from unjust detention are to be repaired.

2. If the thing certainly would have perished at the same time but not by the same natural cause, for example, if two ships perish at the same time, or if the thing perishes by fire with the thief while it would have perished by water at the same hour with the owner, probably it need not be restored, because the owner suffers no damage from this as to the thing; just as neither is he bound to restore who consumed the thing in the same place and around the same time at which, from a natural cause, it would certainly have perished, as from fire, because neither is he the cause of the damage.

3. If, however, the thing would have perished at the same time with the owner from the injustice of another, the thief is bound to restore its price, because the owner suffers damage from the theft: for if the thing had not been taken away, another would have contracted the burden of restoring, and from this other the owner could have recovered it.

4. If the thing would not have perished at morally the same time, the thief is bound to restitution, even if he rescued the thing from danger: for then the thing was unjustly detained for some time by the thief. Thus if someone saves a thing which otherwise was going to perish by fire or waters, he is bound to restore it; he could have not saved it, but, if he saves it, he saves it not for himself but for the owner.

By French civil law (a. 1302, in force among many nations; Italian, a. 1298; Spanish, a. 457), a possessor of bad faith is bound to restitution of the price of the thing in whatever way the thing has perished in his hands. Nevertheless this disposition, insofar as it adds to natural law, can be regarded as a penal clause, whence it does not obligate before, but only after, the sentence of a judge.

305. What must be restored, if the thing during the time of unjust detention had a varied value?

R. Per se the highest value is to be restored, which certainly must be done if the owner is unjustly deprived of this increase, namely: 1. if he himself, since he is vigilant, would have sold the thing at the highest price; 2. if he had to buy another equivalent thing at the highest price; 3. if the unjust possessor became richer from it, for example, because the thing grew in itself, as if a calf matured, for the thing grows for its owner; or 4. on the contrary, if the thing was made worse and would not have been so with the owner.

In practice, however, it will often be difficult to determine whether it is so. In doubt, restitution is to be urged only according to the price of the thing at the time of theft, or according to the greater price for which the owner had to procure another for himself.

306. A possessor of doubtful faith is one who, from a grave and truly probable reason, doubts whether the thing which he detains is his own or another's; whence a negative or very slight doubt does not render a possessor of doubtful faith. Doubtful faith can be antecedent, if it preceded the very receiving of the thing and the possessor received the thing in doubtful faith; or supervening or subsequent, if the possessor began to possess the thing in good faith, but after the receiving of the thing a doubt arose.

A possessor of doubtful faith must diligently investigate the thing; and according as he acts justly or unjustly, he is reduced to a possessor of good or bad faith.

307. In the case of antecedent doubtful faith:

1. if someone occupies a thing occupied here and now by no one, he is bound to inquire concerning the owner and to act in the same way as was said concerning lost things; but if he neglects to inquire, he becomes a possessor of bad faith, and nothing can be retained, but the whole must be handed over to pious causes;

2. if by a doubtful title he takes away a thing and despoils a possessor who is not of bad faith, for example, probably judging that he has a right to part of an inheritance, he is assimilated to a possessor of bad faith and must restore the whole thing to the possessor; because in doubt the condition of the possessor is better. In the case, he ought to have recurred to the judge;

3. if by a legitimate title (for example, donation or purchase) he acquired a thing from a suspect possessor, doubting whether the latter is truly the owner, he is bound to restore at least according to the proportional part of the doubt (that is, according to the weight of reasons) to the probable owner, and failing him to a pious cause: he cannot retain the whole because he began possession without good faith and exposed himself to the danger of possessing another's thing; nor is he probably bound to render the whole, because it is not certain that the thing belongs to another.

Exception: a) if he acquired the thing from a possessor of good faith and after due inquiry an insoluble doubt remains: for then, although perhaps he sinned because of doubtful faith in acquiring, nevertheless he can consider himself as one possessor with his predecessor, so that the possession can be said to have begun in good faith, and the doubt is considered as supervening;

b) if he bought or received the thing with the intention of inquiring concerning the owner and rendering the thing to him as soon as he can be found: for then he begins to possess with good faith, and he can detain the thing until the owner appears. But if he culpably neglected to inquire concerning the owner, and because of the neglected inquiry it is now impossible to solve the doubt, he is now equated with a possessor of bad faith, and according to the proportion of the doubt, that is, according to the weight of reasons, he must restore to the probable owner or to a pious cause, in the same way as was said above.

308. In the case of subsequent doubtful faith: when a doubt has arisen, he is bound from justice diligently to investigate the truth, with that diligence which is proportioned to the value of the thing and the gravity of the doubt; otherwise he becomes as a possessor of bad faith. But he must:

1. before the inquiry is finished, not alienate nor consume the thing, but preserve it;

2. after diligent inquiry has been made, a) if it is certainly or almost morally certainly established that the thing belongs to another, he must restore it in the same way as a possessor of good faith; b) if the doubt perseveres, he can retain the thing and dispose of it, because in doubt the condition of the possessor is better. Therefore he again becomes a possessor of good faith; whence he can use the thing and consume it, as was said concerning a lost thing, indeed sell it, provided that he warn the buyer concerning the doubt, lest the latter be deceived;

3. if he has omitted the inquiry from grave negligence, he becomes a possessor of bad faith and is bound thereafter because of damage perhaps arising, and therefore:

a) if the owner is afterward found, he must repair the whole to him;

b) if because of the neglected investigation it is now impossible to solve the doubt, he is bound to restore according to the proportion of the doubt, when the doubt concerned a right which some determinate man perhaps had in that thing: for then that man is thus deprived of some probable hope of obtaining that thing; but this hope, according to greater or lesser doubt, can be estimated at a price by prudent judgment.

Generally St. Alphonsus thinks that then the quantity to be restored is much less than half the value of the thing, since possession had been begun in good faith. Therefore this restitution must be made to that man (or to his heirs), if he is known; but if he cannot be known, it must be made to the poor or to a pious work.

It is said: if the doubt concerned the right of some determinate man; for if the doubt was not concerning someone determinate, but indeterminately, sin indeed has been committed because of the neglected investigation, and more commonly they judge that even then restitution must be made to the poor; which therefore is to be counseled, for the possessor is in some way in bad faith. Nevertheless the matter is not altogether certain, since some judge that then damage effectively inflicted is not established, since possession was begun in good faith and there is no one who can contend against the possessor concerning the thing possessed.