If a federal official is deliberately violating the Constitution, is it possible no federal court has the power to halt that conduct? Federal judges have been answering “yes” for more than a century— dismissing certain kinds of lawsuits alleging unconstitutional conduct by ruling the lawsuits were not “cases” as meant in the phrase “[t]he Judicial Power shall extend to all Cases” in Article III, Section Two, of the Constitution. For example, in July 2019, the U.S. Court of Appeals for the Fourth Circuit dismissed a lawsuit that the State of Maryland and the District of Columbia brought against President Donald Trump claiming he is deliberately violating the Constitution’s prohibition against receiving emoluments from foreign states. The law...