In the United States, qualified immunity is a legal principle that grants government officials performing discretionary (optional) functions immunity from civil suits unless the plaintiff shows that the official violated "clearly established statutory or constitutional rights of which a reasonable person would have known". It is a form of sovereign immunity less strict than absolute immunity that is intended to protect officials who "make reasonable but mistaken judgments about open legal questions", extending to "all [officials] but the plainly incompetent or those who knowingly violate the law". Qualified immunity applies only to government officials in civil litigation, and does not protect the government itself from suits arising from officials' actions. The U.S. Supreme Court first introduced the qualified immunity doctrine in Pierson v. Ray (1967), a case litigated during the height of the civil rights movement. It is stated to have been originally introduced with the rationale of protecting law enforcement officials from frivolous lawsuits and financial liability in cases where they acted in good faith in unclear legal situations. History and background Pierson v. Ray In Pierson v. Ray (1967), the Supreme Court first “justified qualified immunity as a means of protecting government defendants from ﬁnancial burdens when acting in good faith in legally murky areas. Qualiﬁed immunity was necessary, accord­ing to the Court, because '[a] policeman’s lot is not so unhappy that he must choose between being charged with dereliction of duty if he does not arrest when he had probable cause , and being mulcted in damages if he does.'” Bivens and 42 USC § 1983 lawsuits Qualified immunity frequently arises in civil rights cases, particularly in lawsuits arising under 42 USC § 1983 and Bivens v. Six Unknown Named Agents (1971). Under 42 USC § 1983, a plaintiff can sue for damages when state officials violate their constitutional rights or other federal rights. The text of 42 USC § 1983 reads as follows: Every person who, under color of any statute, ordinance, regulation, custom, or usage, of any State or Territory or the District of Columbia, subjects, or causes to be subjected, any citizen of the United States or other person within the jurisdiction thereof to the deprivation of any rights, privileges, or immunities secured by the Constitution and laws, shall be liable to the party injured ... Similarly, under Bivens v. Six Unknown Named Agents, plaintiffs may sue for damages if federal officials violate their