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.⏎
Ignorantia juris non excusat - "Ignorance of the law is no excuse." Not knowing that one's actions are forbidden by the law is not a defense.⏎
Generalia specialibus non derogant - "The general does not detract from the specific." Specifies that a certain matter of law be covered by the most specific laws pertaining, in the event that broader laws conflict with the specific one.⏎
In claris non fit interpretatio - When a rule is clearly intelligible, there is no need of proposing a (usually extensive) interpretation.⏎
Fiat justitia et pereat mundus - "Let there be justice, though the world perish." Often used as a motto, notably by Ferdinand I, Holy Roman Emperor.⏎