:A norm of equal treatment is cited regularly in the American jurisprudence of property “takings” under the Fifth and Fourteenth Amendments to the Constitution, as a benchmark of fair treatment of owners. According to an increasingly prevalent version of this equality norm, courts should look to parity of treatment among property owners in investigating whether particular regulations “take” property. This essay argues, however, that such an equality norm is misplaced, and that courts should judge fairness by the criterion of expectation—including (...) reasonable expectations of regulation.A norm of equality becomes problematic in the face of the economic theory of the evolution of property. This theory posits that as resources become more congested, their uses carry increasing common pool costs or “externalities”—a scenario that should predictably result in more stringent resource management—up to and including the establishment of regulatory regimes as well as property rights themselves. This evolutionary pattern, however, places earlier and later resource users in different positions vis-à-vis both common pool externalities and regulatory responses, and their different temporal positions fragment the meaning of equal treatment and destabilize it as a jurisprudential norm. This essay argues that while equal treatment may be a benchmark for special or invidious cases, like those relating to civil rights, the great bulk of takings cases involve regulatory responses to congesting resources, where a norm of equal treatment breaks down. Thus, in seeking fair treatment, takings jurisprudence should downplay equality and instead look to the understanding of property as a basis of expectations—but those expectations should include the anticipation of reasonable regulatory responses to resource congestion. (shrink)