The rationale for granting qualified immunity to public officials is the recognition that constitutional law is constantly evolving, and public officials cannot be "expected to predict the future course of constitutional law." Procunier v. Navarette, 434 U.S. 555 (1978). The policy reasons for protecting officials from liability from suit for all conceivable constitutional claims include the need for officials to make decisions without fear of lawsuits, the reluctance to distract officials from their public duties, and the potential that without immunity, people would be deterred from participating in public service. See Scheuer v. Rhodes, 416 U.S. 232 (1974) (explaining that qualified immunity aims to alleviate "the injustice, particularly in the absence of bad faith, of subjecting to liability an officer who is required, by the legal obligations of his position, to exercise discretion," and "the danger that the threat of liability would deter his willingness to execute his office with the decisiveness and the judgment required by the public good").