POWER (OF. poroir, poueir, pocr, Fr. pou volt, It. potcre, power, from potcre, for Lat. posse, to be able). In the English and American law of real property, an authority vested in one or move persons enabling them to make valid conveyances of land, irrespective of their having any interest therein themselves. Such a power may be created by any instrument capable of transferring real estate, but it is moat fre quently conferred by will. It may be general, authorizing the person in whom the power is vested (known as the donee of the power) to convey to any person whatsoever, including him self, or special, where the exercise of the power is restricted to certain persons or classes of per sons. The latter is its more usual form.
The will of the person creating the power (known as the donor) must be strictly observed, not only as to the persons in whose favor it may be exercised, but also as to the time and mode of its execution, whether during the life time of the donee, by deed, or at his death, by last will and testament. The power when duly executed is operative to divest the estate of the person by whom the land is then held and to vest it in one or more others according to its terms. But the deed or will by which this re sult is produced is regarded not as that of the donee executing the power, but as that of the donor by whom it was created, and it derives its efficacy from the instrument by which the power was created. Its operation, therefore, is to invalidate (or, more properly, to 'revoke') the previously existing title and to substitute the title of the new 'appointee' in its stead.
Accordingly, where, as in the ordinary case, the real property is vested in one person and the power of appointment, as it is more fully de scribed, in another, the legal title of the former is held in strict subordination to the power held by the latter, and the clue execution of the power will invalidate any conveyance or incumbrance of the property by such owner.
Powers are described as owing their efficacy to the Statute of Uses, which had the effect of transforming into legal estates the equitable in terests in land, which, under the former practice of conveying property to one person to the use of another, might have been created by parol appointment. Thus the owner of land might give to another the use thereof. reserving to him self or giving to another the right or power of revoking such use or trust and appointing an other in lien thereof. It will he seen that it needed only the touch of the statute, converting these uses into legal estates, to put into effect the elaborate system of powers above described. This system forms an important. and intricate chapter in the law of real property. It has, how ever, been greatly modified by statute in many of the United States. See Sugden, on Powers; Leake, Law of Property in Lund; Tiffany, on Real Property; Williams, Real Property.