The Supreme Court is established by Article III, Section 1 of the Constitution of the United States, which says: "The judicial Power of the United States, shall be vested in one supreme Court .

The size of the Court is not specified; the Constitution leaves it to Congress to set the number of justices.

82 (1851), the Supreme Court held that the status of three slaves who went by steamboat from the slave state of Kentucky to the free states of Indiana and Ohio depended on Kentucky law rather than on Indiana or Ohio law.

Kentucky law made steamboat operators liable for the value of any slaves escaping by the boat.

Writing for the Court, Chief Justice Roger Taney accepted the conclusions of the Supreme Court of Kentucky that refused to rule on the status of the slaves unless they were parties to the lawsuit, and that Kentucky need not apply Indiana or Ohio law under which the three slaves would be considered freed.