罪ざい刑けい法ほう定てい主しゅ義ぎ

noun

nulla poena sine lege; principle of legality in criminal law

A fundamental legal principle that no act can be punished unless it was defined as a crime by law at the time it was committed. Used in legal and academic contexts.

• 罪ざい刑けい法ほう定てい主しゅ義ぎは近きん代だい刑けい法ほうの大だい原げん則そくである。

  The principle of legality is a fundamental principle of modern criminal law.

• 罪ざい刑けい法ほう定てい主しゅ義ぎにより、法ほう律りつがなければ犯はん罪ざいは成せい立りつしない。

  Under the principle of legality, there is no crime without a law.