Inter arma enim silent leges

Inter arma enim silent legēs is a Latin phrase meaning "for among [times of] arms, the laws fall mute," but it is more popularly rendered as "in times of war, the law falls silent."

This maxim was likely first written in these words by Cicero in his published oration Pro Milone, but Cicero's actual wording was Silent enim legēs inter arma.

At the time that Cicero used the phrase, mob violence was common. Armed gangs led by partisan leaders controlled the streets of Rome; nevertheless such leaders were elected to high offices.

Abraham Lincoln's request for an opinion on the suspension of the right to habeas corpus during the American Civil War resulted eventually in the decision, in Ex parte Merryman (1861), of Chief Justice Roger Taney, as a judge of the United States Circuit Court for the District of Maryland: "1. That the president... cannot suspend the privilege of the writ of habeas corpus, nor authorize a military officer to do it. 2. That a military officer has no right to arrest and detain a person not subject to the rules and articles of war... except in aid of the judicial authority, and subject to its control." The United States' government explicitly referred to this maxim within its argument in the case Ex parte Milligan, when it remarked (with an additional reference to Cicero) that "these [amendments of the Bill of Rights], in truth, are all peace provisions of the Constitution and, like all other conventional and legislative laws and enactments, are silent amidst arms, and when the safety of the people becomes the supreme law."

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