n the early 1970s, a federal court injunction prevented the New York Times newspaper from publishing excerpts of a highly controversial, classified Department of Defense study of American military actions in Vietnam, a study popularly referred to as the Pentagon Papers. A former U. S. military analyst, Daniel Ellsberg, had illegally leaked the study to the Times, and later the rival Washington Post. The Supreme Court, however, later refused to keep the newspapers from printing the excerpts, on the grounds that the government cannot, except in extraordinary circumstances, engage in prior restraint, a name referring to the practice of: