What is important about Blackstone is the instruction he provided on reading the sort of text before us today. Blackstone described an interpretive approach that gave far more weight to preambles than the Court allows. Counseling that “[t]he fairest and most rational method to interpret the will of the legislator, is by exploring his intentions at the time when the law was made, by signs the most natural and probable,” Blackstone explained that “[i]f words happen to be still dubious, we may establish their meaning from the context; with which it may be of singular use to compare a word, or a sentence, whenever they are ambiguous, equivocal, or intricate. Thus, the proeme, or preamble, is often called in to help the con-struction of an act of parliament.” 1 Commentaries on the Laws of England 59–60 (1765) (hereinafter Blackstone). In light of the Court’s invocation of Blackstone as “ ‘the preeminent authority on English law for the founding generation,’ ” ante, at 20 (quoting Alden v. Maine, 527 U. S. 706, 715 (1999)), its disregard for his guidance on matters of interpretation is striking.
It is not Scalia, but Stevens, who ignores Blackstone's guidance. As quoted by Stevens himself, Blackstone counsels that preambles be used to resolve meaning, "whenever they are ambiguous, equivocal, or intricate. Stevens argues at length that the preamble must be read to confine the possible meaning of the operative clause because failing to do so would render the preamble without meaning. The Blackstone text he quotes, however, seems to say that the purpose of a preamble is to help resolve ambiguity and offers not other interpretive usage of preambles. Interpreting ambiguity is valuable and using a preamble solely in this way clearly does not render it without meaning.
Scalia, on the other hand, argues:
That requirement of logical connection may cause a prefatory clause to resolve an ambiguity in the operative clause (“The separation of church and state being an important objective, the teachings of canons shall have no place in our jurisprudence.” The preface makes clear that the operative clause refers not to canons of interpretation but to clergymen.) But apart from that clarifying function, a prefatory clause does not limit or expand the scope of the operative clause.
It sems to me that Scalia is taking the exact same view on preambles as Blackstone, they serve to resolve ambiguities and nothing else. (It should be noted that elsewhere Stevens claims that Scalia is inventing a whole new system of interpretation by requiring "only" a logical connection between the preface and the operative clause. Scalia, however, is clearly using this test to articulate the exact same interpretative position proposed by Blackstone and praised by Stevens.