The standard of patentability is a constitutional standard, and the question of the validity of a patent is a question of law.[1171] Congress may authorize the issuance of a patent for an invention by a special, as well as by general law, provided the question as to whether the patentees device is in truth an invention is left open to investigation under the general law.[1172] The function of the Commissioner of Patents in issuing letters patent is deemed to be quasi-judicial in character. Hence an act granting a right of appeal from the Commission to the Court of Appeals for the District of Columbia is not unconstitutional as conferring executive power upon a judicial body.[1173] NATURE AND SCOPE OF THE RIGHT SECURED The leading case bearing on the nature of the rights which Congress is authorized to _secure_ is that of Wheaton _v._ Peters. Wheaton charged Peters with having infringed his copyright on the twelve volumes of "Wheaton's Reports" wherein are reported the decisions of the United States Supreme Court for the years from 1816 to 1827 inclusive. Peters's defense turned on the proposition that inasmuch as Wheaton had not complied with all of the requirements of the act of Congress, his alleged copyright was void. Wheaton, while denying this assertion of fact, further contended that the statute was only intended to _secure_ him in his pre-existent rights at common law. These at least, he claimed, the Court should protect. A divided Court held in favor of Peters on the legal question. It denied, in the first place, that there was any principle of the common law which protected an author in the sole right to continue to publish a work once published. It denied, in the second place, that there is any principle of law, common or otherwise, which pervades the Union except such as are embodied in the Constitution and the acts of Congress. Nor, in the third place, it held, did the word "securing" in the Constitution recognize the alleged common law principle which Wheaton invoked. The exclusive right which Congress is authorized to _secure_ to authors and inventors owes its existence solely to the acts of Congress securing it,[1174] from which it follows that the rights granted by a patent or copyright are subject to such qualifications and limitations as Congress, in its unhampered consultation of the public interest, sees fit to impose.[1175]