It is to be observed that all of these cases had reached the Supreme Court by writ of error to the state courts, and that the federal tribunal had been appealed to upon the ground that the contracts had been impaired by state laws enacted subsequent to the time they were entered into. Had there been no such legislation there would have been no constitutional basis for the exercise of the appellate jurisdiction of the federal court.

In New Orleans Waterworks Co. v. Louisiana Sugar Co.62 the court say: "In order to come within the provision of the Constitution of the United States which declares that no State shall pass a law impairing the obligation of contracts, not only must the obligation of a contract have been impaired, but it must have been impaired by a law of a State. The prohibition is aimed at the legislative power of the State and not at the decisions of its courts."

This doctrine is reaffirmed in Huntington v. Attrill63 and again in Bacon v. Texas.64 In this last case the court, summing up the doctrine, say: "Where the federal question upon which the jurisdiction of this court is based grows out of an alleged impairment of a contract, it is now definitely settled that the contract can only be impaired within the meaning of this clause of the Constitution, and so as to give this court jurisdiction on error to a state court, by some subsequent statute of the State which had been upheld or effect given it by the state court. ... If the judgment of the state court gives no effect to the subsequent law of the State, and the state court decides the case upon grounds independent of that law, a case is not made for review by this court upon any ground of the impairment of a contract. The above cited cases announce this principle."

62 125 U. S. 18; 8 Sup. Ct. Rep. 741; 31 L. ed. 607.

63 146 U. S. 657; 13 Sup. Ct. Rep. 224; 36 L. ed. 1123.

64 163 U. S. 207; 16 Sup. Ct. Rep. 1023; 41 L. ed, 132.

The same doctrine is repeated in Central Land Co. v. Laidley,65 Hanford v. Davies,66 and Weber v. Rogan.67

It would appear, however, that the Supreme Court has shown, strong disposition to find, when possible, an impairing statute, and thus to justify its appellate jurisdiction for the protection of contracts in cases originating in the state courts. The cases of McCullough v. Virginia68 and Muhlker v. New York and Harlem Railroad Co.69 sufficiently illustrate this.