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When the post-Warren Supreme Court began trimming back individual rights, some state courts responded by interpreting analogous or cognate state constitutional provisions to find broader protections, prompting a vigorous debate concerning the legitimacy and interpretive methodology of such state constitutionalism. How can two constitutional provisions, sharing the same language and history, mean different things? This Article looks at that question in the context of so-called prophylactic rules—those specific constitutional rules meant to guide the implementation of broader federal constitutional principles. Miranda ’s warning-and-waiver construct is probably the best known prophylactic rule, but such rules abound, particularly in criminal procedure.

This Article argues that even if states ought to defer to the Supreme Court concerning the meaning of cognate constitutional provisions, such deference is not required in considering the reach of prophylactic rules. Such rules, while constitutional in status, are not vessels of constitutional meaning. Rather, they are a pragmatic means to implement more open-ended constitutional norms and thus, by design, are adjustable where necessary to improve their fitness for that task. The Supreme Court makes such adjustments, and there is no reason why states should not also be able to do so where local conditions suggest the need for a more protective rule. A state’s expansion of a prophylactic rule leaves untouched the meaning of the underlying federal principle, along with the Supreme Court’s prerogative to decide what that meaning is. This Article analyzes such rule expansions under Massachusetts law to develop this point concretely.

But recognizing the latitude of states to expand federal prophylactic rules unilaterally does not necessarily mean that it should be the courts that work this expansion. Again using Massachusetts as the example, this Article argues that, depending upon the conceptual linkage of the rule to its underlying principle, the designed impact of the rule, and the relative judicial vice legislative competence and legitimacy to make the cost-benefit judgments on which rule expansion often rests, the expansion of some prophylactic rules ought to be the province of the state legislature and not the courts. When it is unclear who should decide, this Article argues that a state court should not freeze a rule expansion in constitutional principle, but rather should found its decision in state common law, thus leaving open further reconsideration of the rule’s reach.

Recommended Citation

44 Suffolk U. L. Rev. 415 (2011)