Ex factis jus oritur - "The law arises from the facts." A principle in international law that one must take facts on the ground into account when considering the legality of certain kinds of questions.⏎
Inadimplenti non est adimplendum - "One has no need to respect his obligation if the counter-party has not respected his own." This is used in civil law to briefly indicate a principle (adopted in some systems) referred to as the synallagmatic contract.[3]⏎
Iura novit curia - The judge knows the law (technically, there is no need to "explain the law" or the legal system to a judge/justice in any given petition).⏎
Inter arma enim silent leges - "For among arms, the laws fall silent." A concept that during war, many illegal activities occur. Also taken to mean that in times of war, laws are suppressed, ostensibly for the good of the country.⏎