the mechanics' lien statute secure liens; and, second, that the subsequent change of decision by which that court held that contractors were not included in the mechanic's lien law constituted a law which impaired the obligation of its contract within the meaning of the contract clause of the Constitution of the United States. It therefore assigns as error the action of the court below in not declaring the rights of appellant to be as they existed under the line of judicial decisions at the time such rights accrued.

The title of the Indiana act of March 6, 1883 (c. 115), under which appellant claims to have acquired a lien, was "an act concerning liens of mechanics, laborers and materialmen." A provision of the constitution of Indiana, § 19, art. 4, provides that, "every act shall embrace but one subject and matters properly connected therewith; which subject shall be expressed in the title." The contention is that for many years contractors had been regarded as entitled to a lien under this act and prior acts having a similar title, though it is conceded that the sufficiency of the title had never been expressly decided. On February 18, 1909, the Indiana Supreme Court in the case of Indianapolis Northern Traction Company v. Brennan, 174 Indiana, 1, held that the act of 1883 did not include contractors or sub-contractors. The act was not held to have been unconstitutionally enacted, Wilkes County v. Coler, 180 U. S. 506, nor that contractors and sub-contractors might not have been included among those to whom the privilege of a lien was extended. The decree was confined to the single point that the title did not include contractors. It was therefore a mere construction of the act as not including obligations to contractors as distinguished from obligations to mechanics, laborers and materialmen. This is claimed to have been such a change of decision as to impair the obligation of the contract under which the appellant had constructed

the railway of the Traction Company. Curiously enough, the Supreme Court of Indiana has, pending this appeal, retracted the construction it placed upon the act of 1883 and has held that contractors are within the intent and meaning of the act. Moore-Mansfield Construction Company v. Indianapolis &c. Railway, 179 Indiana, 536. But a change in the opinion of a court as to the proper construction or scope of statute law of a State is not within Art. I, § 10, of the Constitution of the United States, which provides that "no State shall pass any bill of attainder, ex post facto law, or law impairing the obligation of contracts." That provision is a restraint upon the legislative power of the, State, and, as was said by this court, "it concerns the making of laws, not their construction by the courts. It has been so regarded from the beginning." Ross v. Oregon, 227 U. S. 150, 161. There had been no subsequent legislation which in any wise affected liens of contractors.

It has been many times decided that a writ of error will not lie from this court to a state court under § 709, Revised Statutes, on the ground that the obligation of a contract has been impaired by a change in the decision of the court in respect to the meaning and scope of a statute, the validity of which has not been denied. "In order to come within the provision of the Constitution of the United States, which declares that no State shall pass any law impairing the obligation of contracts, not only must the obligation of a contract have been impaired, but it must have been impaired by some act of the legislative power of the State and not by a decision of its judicial department only. The appellate jurisdiction of this court, upon writ of error to a state court, on the ground that the obligation of a contract has been impaired, can be invoked only when an act of the legislature alleged to be repugnant to the Constitution of the United States has been decided by a state court to be valid, and not

when an act admitted to be valid has been misconstrued by the court." Central Land Company v. Laidley, 159 U. S. 103, 109; see also Bacon v. Teras, 163 U. S. 207, 220; Loeb v. Columbia Township, 179 U. S. 472, 493; National Mutual &c. Assn. v. Brahan, 193 U. S. 635. If, therefore, a mere change of decision by a state court in respect of the meaning and scope of a state statute, not claimed to be invalid or repugnant to the Constitution of the United States, does not constitute an impairment of a contract within the meaning of the contract clause of the Constitution, it must follow that a case otherwise within the jurisdiction of a District Court of the United States and reviewable in the Circuit Court of Appeals, is not a case which may come direct to this court merely because in the course of the case a question arises touching the effect of such a change of decision upon the rights of the parties.

Courts of the United States are courts of independent jurisdiction, and when a question arises in a United States court as to the effect of a change in decision which detrimentally affects contract rights and obligations entered into before such change, such rights and obligations should be determined by the law as judicially determined at the time the rights accrued. In every such case the Federal courts, while leaning to the view of the state court as to the validity or interpretation of a law of the State, will exercise an independent judgment and will not necessarily follow state judicial decisions rendered subsequently. Burgess v. Seligman, 107 U. S. 20, 33; Loeb v. Columbia Township, supra.

Under the settled rule it was the duty of the court below when confronted with the question whether appellant had acquired a lien under the act of 1883 to determine for itself the meaning and scope of that act and to declare the rights of that company under the law as it had been judicially determined. The decisions to this effect are VOL. CCXXIV-40

numerous. Some of them are: Folsom v. Ninety-six, 159 U. S. 611, 624; Loeb v. Columbia Township, supra; Jones v. Great Southern Hotel Co., 86 Fed. Rep. 370, affirmed by this court, 193 U. S. 532. If the District Court erred in following the later decision of the Indiana court the error could have been corrected by the Circuit Court of Appeals, and the judgment of the latter court might be reviewed by this court under a writ of certiorari. The cases of Folsom v. Ninety-six, and Jones v. Great Southern Hotel -Company, supra, reached this court through the Circuit Court of Appeals, one by a certified request for an instruction, and the other by certiorari.

The right to bring the case to this court from the District Court by a direct appeal depended upon the question whether the decree denying to appellant the lien it claimed under the law of Indiana, "necessarily and directly involved the construction or application of the Constitution of the United States." Empire &c. Mining Co. v. Hanley, 205 U. S. 225, 232. The change of decision in respect of the scope of the Indiana statutes was not a law of the State impairing the obligation of the contract which is the only basis for the claim that the case is one which involved the construction or application of the Constitution of the United States. We are, therefore, precluded from an examination of the merits of the case, Cosmopolitan Mining Co: v. Walsh, 193 U. S. 460; Knop v. Monongahela &c. Co., 211 U. S. 485, and the appeal

must be dismissed.

STATE OF LOUISIANA v. MCADOO, SECRETARY OF THE TREASURY.

MOTION FOR LEAVE TO FILE PETITION.

Original. Argued April 14, 1914.-Decided June 22, 1914.

The United States may not be sued in the courts of this country without its consent.

Whether the United States is in legal effect a party is not always determined by whether it appears as a party on the record but by the effect of the decree that can be rendered.

A State which happens to operate sugar plantations by its convict labor may not review the action of the Secretary of the Treasury in determining the rate of duty to be collected on foreign sugar any more than any other producer of sugar may do so.

A suit against the Secretary of the Treasury to review his action in determining the rate of duty to be collected, under statutes and treaties, on an imported article, and to mandamus him to collect a specific amount, is in effect a suit against the United States.

Even an importer may not invoke the aid of the courts to clog the wheels of government by attempting to review by mandamus the action of the Secretary of the Treasury in determining the rate of duty to be collected on imported articles.

Determining the rate of duty to be collected under the existing statutes

and treaties on foreign sugar is not a mere ministerial act on the part of the Secretary of the Treasury, but one involving judgment and discretion.

While a public officer may by law, and at the instance of one having a particular legal interest, be required to perform a mere ministerial act not requiring the exercise of judgment or discretion, he may not be so required in respect to matters committed to him by law and requiring the exercise of judgment and discretion.

The courts will not interfere with the ordinary functions of the executive department of the Government.

Application for leave to file a petition for writ of mandamus against the Secretary of the Treasury to compel him to collect a different amount of duty on sugar imported from Cuba under the provisions