So in Marbury v. Chief Justice John Marshall held that the judiciary Act of 1789, upon which the subject-matter jurisdiction of the Court had been asserted, was unconstitutional. But he also went on to say that the Supreme Court possessed the power to exercise jurisdiction over the president of the United States, a conclusion that infuriated President Thomas Jefferson, not least because it was wholly unnecessary to the Court's conclusion and thus clearly dicta. If the Court had no subject matter jurisdiction after all, then there was no need for it to say anything at all about who would have been subject to that hypothetical jurisdiction.

Unknown, Frederick Schauer - Thinkin…, loc. 97