Under the stress of military exigency, upon the actual theatre of war such civil guarantees as the writ of habeas corpus, immunity from search and seizure, etc., may, of course, be suspended. As to this there is no question. There is, however, a serious question whether, when war exists, these rights may, by legislative act or executive proclamation, be suspended in regions more or less remote from active hostilities. This question was raised and carefully considered in the famous Milligan case21 in which the Supreme Court was called upon to pass upon the authority of a military commission, during the Civil War, to try and sentence upon the charge of conspiracy against the United States government one Milligan, who was not a resident of one of the rebellious States, nor a prisoner of war, nor ever in the military or naval service of the United States, but was at the time of his arrest a citizen of the State of Indiana in which state no hostile military operations were then being conducted.

The military commission had been created pursuant to an act of Congress of March 3, 1863, authorizing the suspension of the writ of habeas corpus throughout the United States by the President, but providing that lists of persons, not prisoners of war, held under military authority should be furnished within a given time to the judges of the federal circuit and district courts, and that one so imprisoned whose name was not thus reported might appeal for release to the civil courts.

Five of the justices of the Supreme Court held that Congress was without the constitutional authority to suspend or authorize the suspension of the writ of habeas corpus, and provide military commissions in States outside the sphere of active military operations and with their civil courts open and ready for the transaction of judicial business. The remaining four justices held that Congress had not in fact made legislative provision for the military tribunal in question, but asserted that it possessed the constitutional authority so to do, should it see fit

Shortly speaking, the argument of these four dissenting justices was as follows: "Congress," they said, "has the power not only to raise and support and govern armies, but to declare war. It has, therefore, the power to provide "by law for carrying on war. This power necessarily extends to all power essential to the prosecution of war with vigor and success, except such as interferes with the command of the forces and the conduct of campaigns.

21 Ex parte Milligan, 4 Wall. 2; 18 L. ed. 281.

That power and duty belong to the President as commander-in-chief. . . . We by no means assert that Congress can establish and apply the laws of war where no war has been declared or exists. Where peace exists the laws of peace must prevail. What we do maintain is, that when the nation is involved in war, and some portions of the country are invaded, and all are exposed to invasion, it is within the power of Congress to determine to what States or districts such great and imminent public danger exists as justifies the authorization of military tribunals for the trial of crimes and offenses against the discipline or security of the army or against the public safety. ... It was for Congress to determine the question of expediency."

The fact that the civil courts were open and undisturbed in the execution of their functions is not to be taken as conclusive evidence that the exercise of martial law is unnecessary, it is argued, for, it is pointed out, it may often happen that courts, though open ,and undisturbed in the execution of their functions, may in fact be entirely unable to avert threatened danger, or to punish with adequate promptitude guilty conspirators. Especially in time of civil war, it is observed, the very judges and marshals of the courts may be in more or less active sympathy with the rebels.

It will be seen that, according to the reasoning of these justices, necessity is still the test by which is to be declared the legality of military acts when the citizen is thereby affected either in his person or property. But this necessity, it is argued, is one which it is the province of Congress conclusively to determine, the only limit upon its discretionary powers in this respect being that somewhere war must exist, to which the United States is a party. Whenever, then, such a war does exist, Congress, it is held, if it sees fit, so far as the judiciary may properly prevent, may at once suspend the writ of habeas corpus and generally supersede civil by military government throughout the length and breadth of the land. Its judgment, and not the actual facts of the case, is to determine the presence of that necessity which furnishes the justification for refusing to the individual that protection to his person and property which the civil law affords him.22

Furthermore these four justices assert that the effect of a suspension of the writ of habeas corpus is not simply to deny it to one held in custody, but affirmatively to authorize the executive to arrest as well as to detain.

As opposed to the position taken by these four justices, the majority of the court in the Milligan case assert, first, that no legislative fiat is sufficient to create a necessity for the exercise of martial law when no such necessity in fact exists, and, second, that the circumstance that the ordinary courts are open and undisturbed in the execution of their functions is conclusive evidence of the fact that there is not present a necessity for martial law.

After stating the facts of the case, and declaring that no graver question than the one involved, no one which more nearly concerns the rights of the whole people, was ever before the court, the majority begin their argument by pointing out that the Constitution is a law for rulers and ruled in war as well as in peace, and that "no doctrine, involving more pernicious consequences, was ever invented by the wit of man than that any of its provisions can be suspended during any of the great exigencies of government." With war comes the necessity for the exercise of certain powers latent in the government, but in no case is there created a right upon its part to try and punish the citizen, charged with crime, in any other manner than that provided by law. The opinion continues: