The next important construction of the extent of the federal authority over commerce was that given in the group of cases known as the License Cases,49 decided in 1846. These eases involved state laws fixing conditions of, and requiring licenses for, the sale of certain goods imported from other States. The justices, though unanimous in upholding the state laws, were divided as to the grounds upon which their validity should be vested. By several the concurrent theory was relied upon; by others the police power of the States; while, in some cases, both of these grounds were advanced. There was not, however, a majority of the court in support of either one of these positions. It is remarkable, however, that no dissenting opinion was filed in advocacy of the exclusive power of the Federal Government.

The concurrent theory was most clearly and definitely stated by Taney in his opinion. He said: "The controlling and supreme power over commerce with foreign nations and the several States is undoubtedly conferred upon Congress. Yet, in my judgment, the State may nevertheless, for the safety or convenience of trade, or for the protection of the health of its citizens, make regulations of commerce for its own ports and harbors, and for its own territory; and such regulations are valid unless they come in conflict with a law of Congress." One clause of this sentence seems to indicate the police power as a source of authority for these state commercial regulations; but later on the necessity of resorting to this source of authority is expressly repudiated. The State's au-thority, to make regulations of commerce, he says, "is as absolute as its power to pass health laws, except in so far as it has been restricted by the Constitution of the United States. And when the validity of a state law making regulations of commerce is drawn into question in a judicial tribunal, the authority to pass it cannot be made to depend upon the motives that may be supposed to have influenced the legislature, nor can the court inquire whether it was intended to guard the citizens of the States from pestilence and disease, or to make regulations of commerce for the interest and convenience of trade." However, as has been said, several of the concurring justices were not in agreement with the chief justice upon this point, and found the source of the power of the States to enact the laws in question to be their police powers rather than a concurrent authority to legislate with reference to matters of interstate and foreign commerce.

49 5 How. 504; 12 L. ed. 256.

The position taken by Justice Woodbury is especially worthy of attention, in that it was one which had earlier been suggested by Daniel Webster in an argument in Gibbons v. Ogden, and which approximates the one that has since obtained general acceptance by the court. This is, that the federal power over commerce is 1 exclusive in so far as, from the nature of the case, a uniform regulation is demanded or is appropriate; but that in matters of purely local and particular interest the States may, in the absence of opposing federal statutes, legislate. " I admit." he said, " that, so far as regards the uniformity of a regulation reaching to all the States, it must in these cases, of course, be exclusive. . . . But there is much in connection with foreign commerce which is local within each State, convenient for its regulation and useful to the public, to be acted on by each till the power is abused or some course is taken by Congress conflicting with it."