The railroad having refused to put the rate into effect, the commission applied to the supreme court of the state for a writ of mandamus. In its answer the railroad claimed, among other contentions, that the rate fixed was unreasonably low. The supreme court of the state refused to listen to this contention, saying that the statute by its terms made the order of the commission conclusively reasonable; accordingly it issued the mandamus. By writ of error, the case was brought to the Supreme Court of the United States, which, by a vote of six to three, ordered the decree of the state court vacated, on the ground that the statute as construed by the supreme court of the state was unconstitutional, as a deprivation of property without due process of law. The opinion of the Court, written by Justice Blatchford, has frequently been interpreted to hold, and was indeed interpreted by the dissenting minority to hold, that the judiciary must, to satisfy the requirements of "due process," have the power of final review over the reasonableness of all rates, however fixed. It is doubtful whether the language of the opinion sustains this reading; but the strong emphasis on the place of the judiciary in determining the reasonableness of rates lent color to the contention that Mr. Justice Blatchford was setting up "judicial supremacy." In the course of his opinion, he said: "The question of the reasonableness of a rate of charge for transportation by a railroad company, involving as it does the element of reasonableness both as regards the company and as regards the public, is eminently a question for judicial investigation requiring due process of law for its determination. If the company is deprived of the power of charging reasonable rates for the use of its property, and such deprivation takes place in the absence of an investigation by judicial machinery, it is deprived of the lawful use of its property, and thus in substance and effect, of the property itself without due process of law and in violation of the Constitution of the United States."