Is qualified immunity an affirmative defense that must be pleaded by a defendant?

As a preliminary matter, we note that Nevada makes the same mistake with regard to qualified immunity that it made with sovereign immunity, by contending that it is an issue that impacts the subject matter jurisdiction of the tribal courts. The law is clear that qualified immunity, rather than serving as a jurisdictional bar, "is an affirmative defense that must be pleaded by a defendant official." Harlow v. Fitzgerald, 457 U.S. 800, 815 (1982); see also Blatchford v. Native Village of Noatak, 501 U.S. 775, 786 n.4 (1991) (noting qualified immunity is an affirmative defense that is "wholly distinct" from issues of jurisdiction). We reject Nevada's contention to the contrary.