Source: https://supreme.justia.com/cases/federal/us/222/370/
Timestamp: 2019-04-23 15:59:14+00:00

Document:
A train moving and carrying freight between two points in the same state, but which is hauling freight between points one of which is within and the other without the state, or hauling it through the state between points both without the state, is engaged in interstate commerce, and subject to the laws of Congress enacted in regard thereto. Southern Railway Co. v. United States, 222 U. S. 20.
States, 222 U. S. 20. But while thus governed by the act of Congress, the prohibitions of that act were not operative. This follows by reason of the provisions of § 5 to the following effect: "That this Act shall take effect and be in force one year after its passage."
"On the other hand, it is conceded by the state that the power of the Congress to regulate interstate commerce is plenary, and that, as an incident to this power, the Congress may regulate by legislation the instrumentalities engaged in the business and may prescribe the number of consecutive hours an employee of a carrier so engaged shall be required to remain on duty, and that, when it does legislate upon the subject, its act supersedes any and all state legislation on that particular subject. In fact, these propositions can hardly be said to be debatable in the state courts, since the federal courts, whose decisions are authoritative on questions of this character, have repeatedly announced them as governing principles in determining the validity of regulative legislation concerning carriers of interstate commerce. Escanaba &c. Transp. Co. v. Chicago, 107 U. S. 678; Morgan &c. S.S. Co. v. Louisiana Board of Health, 118 U. S. 455; Nashville &c. R. Co. v. Alabama, 128 U. S. 96; Gladson v. Minnesota, 166 U. S. 427; Lake Shore &c. R. Co. v. Ohio, 173 U. S. 285; Erbe v. Morasch, 177 U. S. 584."

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