Though, as we have seen, there are necessarily many circumstances under which the political power, in behalf of public interests, may interfere with the freedom of action of the individual and the use by him of his own property, in no one of these cases by express constitutional provisions. In the absence of such constitutional provisions, express and implied, the individual thus deprived of property would have no legal claim for damages. To the author it appears proper to group the power of eminent domain under the general police powers of the State.

6 Vol. II. 766.

Now, in exactly the same way in which the civil authorities may by law or through executive action control the activities of the individual and the use of his property in the interest of the public good, the military arm of a government may be employed to preserve the public peace and to secure the execution of the laws.

In European countries, living under written constitutions, provision is quite generally made for the declaration in times of danger of what is called a "state of siege," the effect of which is immediately to suspend the operation of all the ordinary constitutional limitations upon executive power. No similar status is known to American law. The use of the military arm of our States or of the Federal Government in time of peace and upon domestic soil to maintain order and secure the execution of law in no wise operates to suspend civil law or to negate individual rights of liberty and property, any more than the exercise of the ordinary police powers by the State has this effect. The use of the military forces of a State for the maintenance of order and law is, indeed, not dissimilar in purpose and character to the employment by a sheriff of a posse comitatus to assist him in making an arrest, preventing an escape, or serving a writ. In both cases those who exercise authority are obliged to justify whatever acts they may have committed by showing their necessity, or, at least, producing evidence to show that they had reasonable grounds for believing them to be necessary.