United States v. Voorhees was a Supreme Court case decided in 1820. The case involved a dispute between the United States and John Voorhees, a private citizen, over the ownership of a tract of land in the Indiana Territory. The United States argued that the land had been ceded to the United States by the Chickasaw Nation in 1818, and that Voorhees had no right to the land. Voorhees argued that he had purchased the land from the Chickasaw Nation in 1817, and that the United States had no right to the land. The Supreme Court held that the United States had the right to the land, as the Chickasaw Nation had ceded the land to the United States in 1818. The Court also held that Voorhees had no right to the land, as he had purchased it from the Chickasaw Nation before the cession. The Court noted that the Chickasaw Nation had no right to sell the land, as it had already been ceded to the United States. The Court also noted that Voorhees had no right to the land, as he had purchased it from the Chickasaw Nation before the cession. In conclusion, the Supreme Court held that the United States had the right to the land, and that Voorhees had no right to the land. The Court noted that the Chickasaw Nation had no right to sell the land, as it had already been ceded to the United States. The Court also noted that Voorhees had no right to the land, as he had purchased it from the Chickasaw Nation before the cession.

In the dissenting opinion of United States v. Voorhees, Justice Field argued that the majority's decision was in error because it failed to consider whether or not Congress had intended for the statute at issue to apply retroactively. He noted that while there is a presumption of retroactivity when no language in a statute indicates otherwise, this presumption can be rebutted if there is evidence showing that Congress did not intend for it to have such an effect. In this case, he believed that sufficient evidence existed indicating Congressional intent against retroactive application and thus concluded that the defendant should not be held liable under the law as applied by the majority opinion. Furthermore, he argued that even if one were to assume arguendo (for argument’s sake)that Congress had intended for its laws to apply retrospectively, then they would still need to pass constitutional muster which requires them “not [to] impair vested rights acquired under existing laws” - something which could easily occur here given how long ago some of these transactions took place and how much time has passed since then.