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Both originalists and nonoriginalists alike often assume that background assumptions widely held when the Constitution or its amendments were enacted are part of the original meaning of the text. Originalists sometimes appeal to these background assumptions to render the meaning of more abstract words or phrases more determinate; nonoriginalist point to odious or outmoded assumptions as proof that original meaning is objectionable and should be rejected.

In this paper, the author examines the proper role of background assumptions in constitutional interpretation when ascertaining the meaning of the terms, and in constitutional construction when applying this meaning to particular cases and controversies. Rather than present a normative argument on behalf of originalism, he merely tries to identify what the original meaning of the text really is—in particular, the circumstances in which background assumptions become a part of that meaning. While this analysis should be of obvious interest to originalists, it should also be of interest to any nonoriginalist who believes that the original meaning of the text is at least one factor or “modality” of constitutional interpretation to be balanced against other considerations.

In Part I, the author explains how express and implied in fact terms provide the meaning of both written contracts and written constitutions. In Part II, he distinguishes this meaning of the text from the background assumptions that can result in the failure of a contract when circumstances arise about which the text is silent. Unlike contracts, however, with constitutions “failure” is not an option. Further, while background assumptions can be relevant to interpreting the meaning of ambiguous terms in both contracts and constitutions, most sustained disputes over constitutional terms concern, not the interpretation of ambiguity, but the construction of terms whose meaning is vague.

Part III considers how one’s approach to the construction of vague terms will depend on one’s theory of constitutional legitimacy—that is, what makes a constitution “binding.” If, like contracts, the legitimacy of constitutions is based on original consent of the governed then, as with contracts, background assumptions can be viewed as silently conditioning that consent. On the other hand, if constitutional legitimacy is based on the justice of imposing laws on a nonconsenting public, then odious background assumptions are irrelevant to construing vagueness. This divide is illustrated by the antebellum debates over the constitutionality of slavery. Finally, in Part IV, this analysis is applied to three background assumptions: (1) that there are unenumerated natural rights, (2) that there is an unenumerated police power of states, and (3) that certain interpretive methods would be employed by courts.

Publication Citation

103 Nw. U. L. Rev. 615-661 (2009)