COURT MARTIAL. A court authorized by the articles of war, for the trial of all offenders in the army or navy, for military offences. Article 64, directs that general courts martial may consist of any number of commissioned officers, from five to thirteen, inclusively; but they shall not consist of less than thirteen, where the number can be convened, without manifest injury to the service.

2. The decision of the commanding officer who appoints the court, as to the number that can be convened without injury to the service, is conclusive. 12 Wheat. R. 19. Such a court has not jurisdiction over a citizen of the United States not employed in military service 12 John. R. 257. It has merely a limited jurisdiction, and to render its jurisdiction valid, it must appear to have acted within such jurisdiction. 3 S. & R. 590 11 Pick. R. 442; 19 John. R. 7; 1 Rawle, R. 143.

3. A court martial must have jurisdiction over the subject matter of inquiry, and over the person for a want of these will render its judgment null, and the members of the court and the officers who execute its sentence, trespassers. 3 Cranch, 331. See 5 Wheat. 1; 12 Wheat. 19; 1 Brock. 324. Vide Gord. Dig. Laws U. S., art. 3331 to 3357; 2 Story,. L. U. S. 1000; and also the Treatises of Adye, Delafon, Hough, J. Kennedy, M. V. Kennedy, McArthur, McNaghten, Simmons and Tyler on Courts Martial; and 19 John. R, 7; 12 John. R. 257; 20 John. R. 343; 5 Wheat. R. 1; 1 U. S. Dig. tit. Courts, V.