CHAPTER II
THE FIRST ROOT OF RESTITUTION
THE first root of restitution is the possession of another person's property without any just title. This possession may hitherto have been in good faith without any suspicion that the property belonged to somebody else, or it may have been in bad faith with the knowledge that someone else was the rightful owner, or in doubtful faith with doubts about the ownership. The obligations of the possessor of another's property will be different in these three cases. We will treat of them in the three following sections:
SECTION I
Possession of Another's Property in Good Faith
1. When one discovers that he is in possession without any just title of what belongs to someone else, justice requires that he should restore it to the rightful owner, or at least give the owner warning so that he may remove it at his own expense. For justice requires that all should have their own, res clamat domino, and if one knowingly detains what belongs to another against the owner's reasonable wish he commits the sin of theft.
If the possessor of another's property consumed it while he was in good faith, and now when he finds out the truth, he neither has the property itself nor its equivalent, he is bound to nothing, res perit domino. The property no longer exists, and cannot be restored to its true owner; there was no fault committed by consuming what was supposed to belong to the consumer, so there is no obligation to make compensation to the owner for his loss. This is all the more true if the property was destroyed, or perished by accident, or in the ordinary course of nature.
2. If any natural or civil fruits, derived from the property of another, still remain after the possessor has found out that the property belonged to someone else, he must restore them to the owner of the property to whom they belong, for res fructificat domino.