Interdicta seem to have been also called Duplicia in respect of their being applicable both to the acquisition of a possession which had not been had before, and also to the recovery of possession. An Interdict of this class was granted in the case of a vindicatio , or action as to a piece of land against a possessor who did not defend his possession, as, for instance, when he did not submit to a judicium and give the proper sponsiones or satisdationes . A similar interdict was granted in the case of a vindicatio of an hereditas and a ususfructus . Proper security was always required from the person in possession, in the case of an in rem actio , in order to secure the plaintiff against any loss or injury that the property might sustain while it was in the possession of the defendant. By all these Interdicts Possession is protected, and possession in itself, in its immediate form as power, in fact, over a thing.
Possession thus obtains a legal existence, which is simply connected with that fact.
This pure reception of possession among Rights is not perplexed by the consideration of the rightful or wrongful origin of the possession, which origin has no effect with respect to the protection given to possession.