One legal scholar who has made an exhaustive study of qualified immunity is Professor William Baude of the University of Chicago Law School.

In his paper “Is Qualified Immunity Unlawful?” Professor William Baude explains that the Court has over time advanced three justifications for qualified immunity: “One is that it derives from a common law ‘good faith’ defense; another is that it compensates for an earlier putative mistake in broadening the statute; the third is that it provides ‘fair warning’ to government officials, akin to the rule of lenity.”

But all three justifications fail, Baude shows. “There was no such defense, there was no such mistake, and lenity ought not to apply.” And in the early Sec. 1983 cases, the Court rejected the argument that there was or should be a “good faith” defense for officials, instead applying the statute exactly as written. In the 1960s, however, the Court began to read “qualified immunity” into the law. That crack in the dike has led to the situation today where, Baude says, we have virtually unqualified immunity, meaning that suits against government officials almost never succeed.

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