Mr. Justice Field
delivered the opinion of the court.
This case comes before us from the Supreme Court of Tennessee. The plaintiff in error, the defendant in the court below, was indicted in the Criminal Court for the District of Knox County in that State, on the 2d of October, 1874, for the murder of one Mourning Ann Bell, alleged to have been committed in that county on the 7th of March, 1865. To this indictment he pleaded not guilty, and a former conviction for the same offence by a general court-martial regularly' convened for his trial at Knoxville, Tenn., on the 27th of March, 1865, the United States at that time, and when the offence was committed, occupying with their armies East Tennessee ás a military district, and the defendant being a regular soldier in their military service, subject to the articles of war, military orders, and such military laws as were there in force by their authority. The plea states that before the said courhmartial thus convened at Knoxville, then the head-quarters of the military district, the defendant was arraigned upon a charge of murder, in having killed the same person mentioned in the indictment, and that he was afterwards, on the 9th of May, 1865, tried and convicted of the offence by that tribunal, and sentenced to death by hanging, and that said sentence is still standing as the judgment of the court-martial, approved as required by law in such cases, without any other or further action thereon. In consideration of the premises, and by reason of the said trial and conviction, and of the jeopardy involved in said proceedings, the defendant prays that the indictment may be quashed.
Objection being taken by demurrer to this plea, it was twice amended by leave of the court. The first amendment consisted in setting forth with particularity the organization of the court-martial, and the proceedings before it upon which the defendant was convicted of the offence with which he is charged in the indictment. The second amendment consisted in adding an averment that the offence charged was committed, and that the court-martial which tried the defendant was. held in time of civil war, insurrection, and rebellion.
To the plea thus amended a demurrer was sustained, on two grounds; one of which was, in substance, that the defendant's conviction of the offence charged by a court-martial, under the laws of the United States, on the 9th of May, 1865, was not a bar to the indictment for the same offence; because by the murder alleged he was also guilty of an offence against the laws of Tennessee.
The defendant, was thereupon put upon his trial in the Criminal Court, convicted of murder, and sentenced to death. On appeal to the Supreme Court of the State the judgment was affirmed.
Pending the appeal to that court, the defendant was brought before the Circuit Court of the United States for the Eastern District of Tennessee on habeas corpus, upon a petition stating that he was unlawfully restrained of his liberty and imprisoned by the sheriff of Knox County, upon the charge of murder, for which he had been indicted, tried, and convicted, as already mentioned; and setting forth his previous conviction for the same offence by a court-martial, organized under the laws of the United States, substantially as in the plea to the indictment. The sheriff made a return to the writ, that he held the defendant upon a capias from the criminal court for the offence of murder, and also upon an indictment for assisting a. prisoner in making his escape from jail. The Circuit Court being of opinion that so far as the defendant was held under the charge of murder, he was held in contravention of the Constitution and laws of the United States, ordered his release from custody upon that charge. His counsel soon afterwards presented a copy of this order to the Supreme Court of Tennessee, and moved that he be discharged. That court took the motion under advisement, and disposed of it together with the appeal from the Criminal Court, holding, in a carefully prepared opinion, that the act of Congress of Feb. 5, 1867, under which the writ of habeas corpus was issued, did not confer upon the Federal Court,- or upon any of its judges, authority to interfere with the State courts in the exercise of their jurisdiction over offences against the laws of the State,' especially when, as in this case, the question raised by the pleadings was one which would enable the accused to have a revision of their action by the Supreme Court of the United States; and, therefore, that the order of the Circuit Court in directing the discharge of the defendant was a nullity. And upon the question of the effect of the conviction by the court-martial, it held that the conviction constituted no bar to the indictment in the State court for the same offence, on the ground that the crime of murder, committed by the defendant whilst a soldier in the military service, was not less an offence against the laws of the State, and punishable by its tribunals, because it was punishable by a court-martial under the laws of the United States.
The case being brought to this court, it has been argued as though its determination depended upon the construction given to the thirtieth section of the act of Congress of March 3,1863, to enroll and call out the national forces, the defendant's coun sel contending that the section vested in general courts-martial and military commissions the right to punish for the offences designated therein, when committed in time of war, by persons in the military service of the United States, and subject to the articles of war, to the exclusion of jurisdiction over them by the State courts. That section enacts: —
" That in time of war, insurrection, or rebellion, murder, assault and battery with an intent to kill, manslaughter, mayhem, wounding by shooting or stabbing with an intent to commit murder, robbery, arson, burglary, rape, assault and battery with an intent to commit rape, and larceny, shall be punishable by the sentence of a general court-martial or military commission, when committed by persons who are in the military servioe of the United States, and subject to the articles of war; and the punishment for such offences shall never be less than those inflicted by the laws of the State, territory, or district in which they may have been committed." 12 Stat. 736.
The section is part of an act containing numerous provisions for the enrolment of the national forces, designating who shall constitute such forces; who shall be exempt from military service; when they shall be drafted for service; when substitutes may be allowed; how deserters and spies and persons resisting the draft shall be punished; and many other particulars, having for their object to secure a large force to carry on the then existing war, and to give efficiency to it when called into service. It was enacted not merely to insure order and discipline among the men composing those forces, but to protect citizens not in the military service from the violence of soldiers. It is a matter well known that the march even of an army not hostile is often accompanied with acts of violence and pillage by straggling parties of soldiers, which the most rigid discipline is hardly able to prevent. The offences mentioned are those of most common occurrence, and the swift and summary justice of a military court was deemed necessary to restrain their commission.
But the section does not make the jurisdiction of the military tribunals exclusive of that of the State courts. It does not declare that soldiers committing the offences named shall not be amenable to punishment by the State courts. It simply declares that the offences shall be " punishable," not that they shall be punished by the military courts; and this is merely saying that they may be thus punished.
Previous to its enactment, the offences designated were punishable by the State courts, and persons in the military service who committed them were delivered over to those courts for trial; and it contains no words indicating an intention on the part of Congress to take from them the jurisdiction in this, respect which they had always exercised. With the known hostility of the American people to any interference by the military with the regular administration of justice in the civil courts, no such intention should be ascribed to Congress in the absence of clear and direct language to that effect.
We do not mean to intimate that it was not within the competency of Congress to confer exclusive jurisdiction upon military courts over offences committed by persons in the military service of the United States. As Congress is expressly authorized by the Constitution " to raise and support armies," and " to make rules for the government and regulation of the land and naval forces," its control over the whole subject of the formation, organization, and government of the national armies, including therein the punishment of offences committed by persons in the military service, would seem to be plenary. All we now affirm is, that by the law to which we are referred, the thirtieth section of the Enrolment Aet, no such exclusive jurisdiction is vested in the military tribunals mentioned. No public policy would have been sub-served by investing them with such jurisdiction, and many reasons may be suggested against it. Persons in the military service could not have been taken from the army by process of the State courts without the consent of the military authorities ; and therefore no impairment of its efficiency could arise from the retention of jurisdiction by the State courts to try the offences. The answer of the military authorities to any such process would have been, "We are empowered to try and punish the persons who have committed the offences alleged, and we will see that justice is done in the premises." Interference with the army would thus have been impossible; and offences committed by soldiers, discovered after the army had marched to a distance, when the production of evidence before a court-martial would have been difficult, if not impossible, or discovered after the war was over and the army disbanded, would not go unpunished. Surely Congress could not have intended that in such cases the guilty should go free.
In denying to the military tribunals exclusive jurisdiction, under the section in question, over the offences mentioned, when committed by persons in the military service of the United States and subject to the articles of war, we have reference to them when they were held in States occupying, as members of the Union, their normal and constitutional relations to the Federal government, in which the supremacy of that government was recognized, and the civil courts were open and in the undisturbed exercise of their jurisdiction. When the armies of the United States were in the territory of insurgent States, banded together in hostility to the national government and making war against it, in other words, when the armies of the United States were in the enemy's country, the military tribunals mentioned had, under the laws of war, and the authority conferred by the section named, exclusive jurisdiction to try and punish offences of every grade committed by persons in the military service. Officers and soldiers of the armies of the Union were not subject during the war to the laws of the enemy, or amenable to his tribunals for offences committed by them. They were answerable only to their own government, and only by its laws, as enforced by its armies, could they be punished.
It is well settled that a foreign army permitted to march through a friendly country, or to be stationed in it, by permission of its government or sovereign, is exempt from the civil and criminal jurisdiction of the place. The sovereign is understood, said this court in the celebrated case of The Exchange (7 Cranch, 139), to cede a portion of his territorial jurisdiction when he allows the troops of a foreign prince to pass through his dominions: " In such case, without any express declaration waiving jurisdiction over the army to which this right of passage has been granted, the sovereign who should attempt to exercise it would certainly be con sidered as violating his faith. By exercising it, the purpose for -which the free passage was granted would be defeated, and a portion of the military force of a foreign independent nation would be diverted from those national objects and duties to which it was applicable, and would be withdrawn from the control of the sovereign whose power and whose safety might greatly depend en retaining the exclusive command and disposition of this force. The grant of a free passage, therefore,. implies a waiver of all jurisdiction over the troops during their passage, and permits the foreign general to use that discipline and to inflict those punishments which the government of his army may require."
If an army marching through a friendly country would thus be exempt from its civil and criminal jurisdiction, a fortiori would an army invading an enemy's country be exempt. The fact that war is waged between two countries negatives the possibility of jurisdiction being exercised by the tribunals of the one country over persons engaged in the military service of the other for offences committed while in such service. Aside from this want of jurisdiction, there would be something incongruous and absurd in permitting an officer or soldier of an invading army to be tried by his enemy, whose country he had invaded.
The fact that when the offence was committed, for which the defendant was indicted, the State of Tennessee was in the military occupation of the United States, with a military gov ernor at its head, appointed by the President, cannot alter this conclusion. Tennessee was one of the insurgent States, forming the organization known as the Confederate States, against which the war was waged. Her territory was enemy's country, and its character in this respect was not changed until long afterwards.
The doctrine of international law on the effect of military occupation of enemy's territory upon its former laws is well established. Though the late war was not between independent nations, but between different portions of the same nation, yet haying taken the proportions of a territorial war, the insurgents having become formidable enough to be recognized as belligerents, the same doctrine must be held to apply. The right to govern the territory of the enemy during its military occupation is one of the incidents of war, being a consequence of its acquisition; and the character and form of the government to be established depend entirely upon the laws of the conquering State or the orders of its military commander. By such occupation the political relations between the people of the hostile country and their former government or sovereign are for the time severed; but the municipal laws — that is, the laws which' regulate private rights, enforce contracts, punish crime, and regulate the transfer of property — remain in full force, so far as they affect the inhabitants of the country among themselves, unless suspended or superseded by the conqueror. And the tribunals by which the laws are enforced continue as before, unless thus changed. In other words, the municipal laws of the State, and their administration, remain in full force so far as the inhabitants of the country are concerned, unless changed by the occupying belligerent. Halleck, Int. Law, c. 38.
This doctrine does not affect, in any respect, the exclusive character of the jurisdiction of the military tribunals over the officers and soldiers of the army of the United States in Tennessee during the war; for, as already said, they were not subject to the laws nor amenable to the tribunals of the hostile country. The laws of the State for the punishment of crime were continued in force only for the protection and benefit of its own people. As respects them, the same acts which constituted offences before the military occupation constituted offences afterwards ; and the same tribunals, unless superseded by order of the military commanders, continued to exercise their ordinary jurisdiction.
If these views be correct, the plea of the defendant of a former conviction for the same offence by a coiirt-martial under the laws of the United States was not a proper plea in the case. Such a plea admits the jurisdiction of the criminal court to. try the offence, if it were not for the former conviction. Its inapplicability, however, will not prevent our giving effect to the objection which the defendant, in this irregular way, attempted to raise, that the State court had no jurisdiction to try and punish him for the offence alleged. The judgment and conviction in the criminal court should have been set aside, and the indictment quashed for want of jurisdiction. Their effect was to defeat an act done, under the authority of the United States, by a tribunal of officers appointed under the law enacted for the government and regulation of the army in time of war, and whilst that army was in a hostile and conquered State. The judgment of that tribunal at the time it was rendered, as well as the person of the defendant, were beyond the control of the State of Tennessee. The authority of the United States was then sovereign and their jurisdiction exclusive. Nothing which has since occurred has diminished that authority or impaired the efficacy of that judgment.
In thus holding, we do not call in question the correctness of the general doctrine asserted by the Supreme Court of Tennessee, that the same act may, in some instances, be an offence against two governments, and that the transgressor may be held liable to punishment by both when the punishment is of such a character that it can be twice inflicted, or by either of the two governments if the punishment, from its nature, can be only once suffered. It may well be that the satisfaction which the transgressor makes for the violated law of the United States is no atonement for the violated law of Tennessee. But here there is no case presented for the application of the doctrine. The laws of Tennessee with regard to offences and their punishment, which were allowed to remain in force during its military occupation, did not apply to the defendant, as he was at the time a soldier in the army of the United States and subject to the articles of war. He was responsible for his conduct to the laws of his own government only as enforced by the commander of its army in that State, without whose consent he could not even go beyond its lines. Had he been caught by the forces of the enemy, after committing the offence, he might have been subjected to a summary trial and punishment by order of their commander; and there would have been no just ground of complaint, for the marauder and the assassin are not protected by any usages of civilized warfare. But the courts of the State, whose regular government was superseded, and whose laws were tolerated from motives of convenience, were without jurisdiction to deal with him.
This conclusion renders it unnecessary to consider the question presented as to the effect to be given to the order of the Circuit Court of the United States directing the discharge of the defendant. It is sufficient to observe that, by the act of Congress of Feb. 5, 1867, the several courts of the United States, and their judges, in their respective jurisdictions, have, in addition to the authority previously conferred, power to grant writs of habeas corpus in all cases upon petition of any person restrained of his liberty in violation of the Constitution or of any law of the United States ; and if it appear, on the hearing had upon the return of the writ, that the petitioner is thus restrained, he must be forthwith discharged and set at liberty. Ex parte Yerger, 8 Wall. 101.
It follows, from the views expressed, that the judgment of the Supreme Court of Tennessee must be reversed, and the cause remanded with directions to discharge the defendant from custody by the sheriff of Knox County on the indictment and conviction for murder in the State court. But as the defendant was guilty of murder, as clearly appears not only by the evidence in the record in this case, but in the record of the proceedings of the court-martial, — a murder committed, too, under circumstances of great atrocity, — and as he was convicted of the crime by that court and sentenced to death, and it appears by his plea that said judgment was duly approved and still remains without any action having been taken upon it, he may he delivered up to the military authorities of the United States, to he dealt with as required by law.
So ordered.
The same exemption from the civil and criminal jurisdiction of the place is extended to an armed vessel of war entering the ports of a friendly country by permission of its government, or seeking an asylum therein in distress. She is accorded the rights of exterritoriality, and is treated as if constituting a part of the territory of her sovereign. " She constitutes," said the court in the same case, "a part of the military force of her nation, acts under the immediate and direct command of the sovereign, is employed by him in national objects. He has many and powerful motives for preventing those objects from being defeated by the interference of a foreign State. Such interference cannot take place without afiecting his power and his dignity. The implied license, therefore, under which such vessel enters a friendly port, may reasonably be construed, and it seems to the court ought to be construed, as containing an exemption from the jurisdiction of the sovereign within whose territory she claims the rights of hospitality." 7 Cranch, 144. See also Cushing on Bellig erent Asylum, in Opinions of Att'ys-Gen., vol. vii. p. 122; Halleck, Int. Law c. 7, sect. 25.