waiver, discharge, release - a formal written statement of relinquishment

fix - an exemption granted after influence (e.g., money) is brought to bear; "collusion resulted in tax fixes for gamblers"

official immunity - personal immunity accorded to a public official from liability to anyone injured by actions that are the consequence of exercing official authority

sovereign immunity - an exemption that precludes bringing a suit against the sovereign government without the government's consent; "the doctrine of sovereign immunity originated with the maxim that the king can do no wrong"

testimonial immunity, use immunity - an exemption that displaces the privilege against self-incrimination; neither compelled testimony or any fruits of it can be used against the witness who therefore can no longer fear self-incrimination