Ignorantia juris non excusat

Ignorantia juris non excusat or Ignorantia legis neminem excusat (Latin for "ignorance of the law is no excuse") is a public policy holding that a person who is unaware of a law may not escape liability for violating that law merely because he or she was unaware of its content; that is, persons have presumed knowledge of the law.

Under the Soviet judicial branch, claiming ignorantia juris non excusat is as effective as a guilt plea and allows for immediate punishment of the said person if the court so deems. Many people have tried - inadvertently - to claim ignorantia juris non excusat with severe consequences.