In this post I explain why “Dictionaries” rank 17th on my list of the “Top 21 Sources of Legislative History.” Click here for a brief overview of the basis for these rankings.
17. Dictionaries: In 1994, the Harvard Law Review published an article that chronicles the dramatic rise of dictionaries as interpretative aids to the Supreme Court over the last century. The article points to the 600+ dictionary references by the Supreme Court over the last two centuries as proof of this phenomenon. This trend shows no signs of slowing either; a recent study published in the Marquette Law Review (here) reveals that since 2000, the Supreme Court has used a dictionary in 225 separate opinions to define a total of 295 words.
A. The Rise of the Dictionary in Judicial Opinions
The popularity of dictionaries as a source for interpreting legal terms of art and other words found in statutes may be due, in part, to their availability and ease of use (it’s a lot easier to pull a dictionary off the shelf and flip through alphabetized words than it is to parse through reams of legislative documents when selecting an acceptable definition). Others claim that the wide variety of dictionaries published each year (e.g., Oxford’s English, Merriam–Webster’s, Black’s Law Dictionary, etc.) provide an enticing platter of competing definitions from which those tasked with defining a statutory term may “cherry pick” the definition that best supports their desired outcome. As Adam Liptak of the New York Times pointed out in a recent article:
In May  alone, the justices cited dictionaries in eight cases to determine what legislators had meant when they used the words “prevent,” “delay” and “report.” Over the years, justices have looked up both perfectly ordinary words (“now,” “also,” “any,” “if”) and ones you might think they would know better than the next guy (“attorney,” “common law”).
Finally, dictionaries are persuasive because they allow judges to avoid the appearance of judicial activism. Whereas merely defining a statutory term based on common sense or some general notion of fairness may seem arbitrary, using a dictionary definition to reach the same outcome creates the appearance of objectivity.
B. The Dictionary Act
Although less popular than its commercial counterparts, Congress’s Dictionary Act does provide an authoritative, but limited, set of default definitions for certain words commonly used in other statutes. For example, where Congress writes a statute that applies to all “persons,” but fails to define who (or what) exactly qualifies as a “person,” the statute's silence on the matter suggests that its drafters intended for the Dictionary Act's definition of the term to apply. (The Dictionary Act defines "person" as including not only living, breathing human beings, but also legal "persons" such as corporations.)
C. The Inadequacy of Dictionaries as an Interpretive Aid
Despite the recent rise in popularity of dictionaries as an interpretive aid, dictionaries remain relatively unimportant for several reasons. First, dictionaries are no more likely to accurately reflect the meaning intended by the Legislature than the statute’s actual legislative history. The editor at large of the Oxford English Dictionary noted, “I think that it’s probably wrong, in almost all situations, to use a dictionary in the courtroom,” adding, “Dictionary definitions are written with a lot of things in mind, but rigorously circumscribing the exact meanings and connotations of terms is not usually one of them.”
Judge Learned Hand expressed a similar concern when he wrote, “It is one of the surest indexes of a mature and developed jurisprudence not to make a fortress out of the dictionary; but to remember that statutes always have some purpose or object to accomplish, whose sympathetic and imaginative discovery is the surest guide to their meaning.” Cabell v. Markham, 148 F.2d 737, 739 (2d Cir. 1945).
Finally, the meaning of a word is shaped over time by the context in which people use it. Dictionaries merely reflect the popular use of a given word at that particular period in time. But this context can, and often does, change over time. If one were to consult a dictionary to help make an educated guess about Congress's intended meaning of a particular statutory term, logically, the definition in a dictionary published around the same time that the statute in question was drafted would more accurately reflect the term's intended meaning than a definition plucked from a subsequent edition. Yet, in Buckannon Board & Care Home v. West Virginia Department of Health & Human Resources this was not the case. Here, the Court was asked to interpret the term “prevailing party” as used by Congress in its civil rights legislation passed during the 1960s and '70s.
In drafting these laws, Congress might have referred to the 1968 revised 4th Edition of Black’s Law Dictionary when it placed the term “prevailing party." According to this edition, a prevailing party is “one of the parties to a suit who successfully prosecutes the action or successfully defends against it, prevailing on the main issue, even though not to the extent of his original contention.” 
Yet, when tasked with defining this term of art, Chief Justice Rehnquist instead relied on the 7th Edition of Black’s Law Dictionary, which was published decades after the statutes at issue were enacted--1999. This led to a peculiar result: “prevailing party” was given a much different meaning than the one that existed when the term that was originally drafted into the law. The 7th Edition defined “prevailing party” as:
“[a] party in whose favor a judgment is rendered, regardless of the amount of damages awarded (in certain cases, the court will award attorney's fees to the prevailing party).—Also termed successful party.” This view that a “prevailing party” is one who has been awarded some relief by the court can be distilled from our prior cases.
In short, dictionaries have emerged as an easy, popular tool for interpreting undefined terms found in statutes. Dictionaries nevertheless rank relatively low on my list because (1) they are just as susceptible to abuse as traditional sources of legislative history; (2) they are not written by or for a legal audience; and (3) the meaning of words change over time, meaning definitions plucked from a different time period than the one in which the relevant statute was drafted do not accurately reflect the intended meaning of that term. As a result, dictionaries rank 17th on my list of sources of the top 21 sources of legislative history.
The following lists the “Top 21 Sources of Legislative History” (1 = most important; 21 = least important):
- Conference Committee Reports
- Committee Debates and Bill Mark-ups
- Committee Reports
- The Status of the Person Speaking—Sponsor, Committee Chairman, Floor Leader, Etc.
- Accepted and Rejected Amendments
- Floor Debates
- Planned Colloquy
- Transcripts of Discussions at Committee Hearings
- Prepared Statements on Submission of a Bill, in Committee Hearings, and at the Time of Floor Debates
- Revised and Amended Statements
- Actions on and Discussions About Separate Bills on the Same Topic
- Prior Relevant Administrative Action or Judicial Decisions, with or without Congressional Acknowledgement
- Executive Branch Messages and Proposals Whether from the President, Cabinet Secretaries, or from Independent Agencies
- Analysis of Bills Legislative Counsel
- Analysis of Bills by Relevant Executive Departments
- Related Statutes, Provisions, and Terms (click here)
- Statements by Executive Branch Administrators (click here)
- Statements and Submissions by Lobbyists (click here)
- Subsequent or Prior Unrelated, but Conflicting Legislation (click here)
- Recorded Votes (click here)
 1 U.S.C. § 1 (2006).
 Id. (defining the term “person” as including “corporations” and various other legal entities “unless the context [of the Act] indicates otherwise”).
 Buckhannon Bd. & Care Home v. W. Va. Dep't of Health & Human Res., 121 S. Ct. 1835, 1839 (2001) (alterations in original) (quoting Black's Law Dictionary 1145 (7th ed. 1999)).