United States v. DeWitt was a United States Supreme Court case that dealt with the issue of whether a federal statute that prohibited the sale of liquor on Indian reservations was constitutional. The Court held that the statute was constitutional, as it was within the scope of Congress’s power to regulate commerce with Indian tribes. The case arose when the defendant, DeWitt, was charged with violating the federal statute by selling liquor on an Indian reservation. DeWitt argued that the statute was unconstitutional, as it was an infringement on the sovereignty of the Indian tribes. The Supreme Court disagreed, holding that Congress had the power to regulate commerce with Indian tribes, and that the statute was a valid exercise of that power. The Court noted that the statute was not an infringement on the sovereignty of the Indian tribes, as it did not interfere with their internal affairs. Rather, it was a valid exercise of Congress’s power to regulate commerce with Indian tribes, and thus was constitutional. In conclusion, the Supreme Court held that the federal statute prohibiting the sale of liquor on Indian reservations was constitutional, as it was within the scope of Congress’s power to regulate commerce with Indian tribes.

In United States v. DeWitt, the Supreme Court was asked to decide whether a federal tax on sales of distilled spirits applied to those sold before the law took effect. The majority opinion held that it did not, finding that Congress had no power under the Constitution to impose taxes with retroactive effect. Justice Field dissented from this decision, arguing that Congress had clear authority under Article I of the Constitution to enact laws with retrospective operation and taxation was one such area where they could do so without infringing upon any rights or privileges granted by state governments. He further argued that if Congress were prohibited from taxing past transactions then it would be impossible for them to raise revenue in order for them to carry out their constitutional duties and obligations as laid out in Article I Section 8 of the Constitution.