On the day of the attack on Pearl Harbor, the Governor of Hawaii suspended the writ of habeas corpus and declared martial law in that territory, acting under authority of the Organic Act of Hawaii. At the Governor's request, the Commanding General of the Hawaiian Department of the Army proclaimed himself Military Governor of the Islands, and established military tribunals to try all violations ,of existing federal laws and military regulations thereafter to be promulgated. The following day all civil courts were closed, and the next day the President approved the Governor's action. One week later, the law courts were permitted to resume jurisdiction of non-jury civil suits; this jurisdiction was gradually widened in the ensuing months to include all cases except those involving violation of military regulations. Martial law was terminated in October of 1944.
CONSTITUTIONAL LAW-MARTIAL LAW-TRIAL OF CIVILIANS BY MILITARY TRIBUNALS IN HAWAII,
Mich. L. Rev.
Available at: https://repository.law.umich.edu/mlr/vol45/iss1/5