Mercer Law Review, Vol. 51, No. 2 (Winter 2000), pp. 583-601


Mt. Healthy City School District Board of Education v. Doyle is among the most important, and least discussed, cases in constitutional tort law. It stands for the abstract principle that the "but-for" rule of causation, which is the usual test in common-law torts, applies in constitutional torts as well. Doyle, a nontenured school teacher, quarreled with another teacher, with school employees, and with students. Two specific incidents deserve mention. First, on one occasion he "made an obscene gesture to two girls in connection with their failure to obey commands made in his capacity as cafeteria supervisor." Second, after the principal circulated a memorandum on a teacher dress code, he called a local radio station to criticize the administration. "[C]iting 'a notable lack of tact in handling professional matters which le[ft] much doubt as to [his] sincerity in establishing good school relationships,'" and giving the radio station incident and the obscene gesture incident as examples, the school district declined to offer him a contract for the next school year.

Doyle sued under 42 U.S.C. § 1983, which authorizes victims of constitutional violations to sue for damages or injunctive relief. Though Doyle was able to show that protected speech played a part in the decision, a unanimous Court held that he could not recover damages for the discharge if the government could prove that he would have been fired anyway, for constitutionally permissible reasons. Otherwise, Doyle would be "in a better position as a result of the exercise of constitutionally protected conduct than he would have occupied had he done nothing." The Court adopted a two-part test for causation in mixed motive cases. First, the plaintiff must show that the "conduct was constitutionally protected, and that his conduct was a 'substantial factor'--or, to put it in other words, that it was a 'motivating factor' in the Board's decision. Once the plaintiff meets the substantial factor test, the burden of proof shifts to the defendant to show "by a preponderance of the evidence that it would have reached the same decision ... even in the absence of the protected conduct." The Court's rule is a variant of the but-for test that governs most cause-in-fact issues in the common law of torts, differing only in its allocation of the burden of proof. Unlike the issue of whether speech is protected by the First Amendment, which is a question of law for the court, the causation issue is for the jury, subject to the customary judicial oversight for reasonableness.

This Article argues that Mt. Healthy was wrongly decided and therefore should not be applied either in determining liability or in assessing damages. It should be replaced by a rule that allows the plaintiff to recover full damages whenever the constitutional violation was sufficient to cause them. Part II focuses on the role of causation in tort law. Examining Mt. Healthy from the perspective of general tort theory, I argue that the ruling is at odds with the fairness and deterrence goals of tort law. Part III shifts to the special features of the constitutional tort context. Quite apart from the general principles of tort law, the special role of constitutional tort law as part of the system of constitutional remedies justifies a more plaintiff-friendly causation rule for constitutional torts. In Part IV, I return to the First Amendment origins of Mt. Healthy and argue that certain distinctive features of retaliation cases, in particular the fragility of First Amendment rights, justify a special sufficient cause rule in this context, even if such a rule were rejected for other constitutional claims. Notice that, while the narrow focus of Part IV is the First Amendment retaliation doctrine, the rest of the analysis is relevant across the whole range of constitutional tort suits.