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What is Legislative History?

Legislative history is the record of Congressional discussion that occurred before a law was passed. It includes hearings, committee reports, and floor debates--documents included in the legislative history database--which help put the intent behind the law in context. However, not all types of legislative history carry equal weight. Courts of law confer different degrees of importance to different types of legislative history documents. For example, a committee report is more important than a statement from an opponent of the legislation, based on the assumption that the committee has minutely examined the legislation, while the opponent may exaggerate the actual power of the legislation. The significance of legislative history documents, in descending order of importance, is as follows:
  1. Committee Reports
  2. a. Statements of sponsors to the whole chamber
    b. Explanations of the committee chair
  3. a. Committee hearings
    b. Statements in general debate
  4. a. Statements of members of the opposition
    b. Amendments or language rejected in committee or on the floor
Managers can incorporate this hierarchy into their own evaluation of the relevance of legislative history documents (for examples specific to wilderness, see Meyer 19991 and Meyer 20002). Legally, legislative history is used to clarify the intent behind legislation only when the meaning of the legislation itself does not follow the "plain meaning rule." Essentially, if the language of a statute is unambiguous, then interpretation must be based solely on the wording of the statute, without reference to outside sources of information. In situations where the pertinent legislation is conflicted or ambiguous, legislative history may serve as a reference point for understanding the intent of Congress. Understanding the intent behind ambiguous wording "gives wilderness managers a basis for consistent and appropriate decision-making regarding nonconforming wilderness uses"1.

Legislative history may also provide insight into the reasoning behind allowing nonconforming uses in wilderness. What were the specific considerations that led Congress to write legislation the way it did? What problems was Congress trying to avoid or solve?

Example: The Wilderness Act of 1964 describes wilderness as "untrammeled by man" and "with the imprint of man's works substantially unnoticeable." The Forest Service interpreted this to mean that areas with any sign of human activities, such as roads or previously logged areas, would not be considered for wilderness designation (the "purity doctrine"). The Endangered American Wilderness Act of 1978 states that some areas were not "adequately protected or fully studied," but makes no direct reference to the concept of "purity." A committee report in the legislative history, however, specifically refutes the "purity" concept in the context of potential wilderness: "Generally, the committee believes that the so-called 'purity' concept of wilderness long adhered to by the Forest Service, is unnecessarily restrictive and should be abandoned"3.

For more information about legislative history and the legislative history database, read Improving Wilderness Stewardship Through Searchable Databases of U.S. Legislative History and Legislated Special Provisions, by David R. Craig, Peter Landres and Laurie Yung in the August 2010 issue of the International Journal of Wilderness.


  1. Meyer, S. S. (1999). The Role of Legislative History in Agency Decision Making. A Case Study of Wilderness Airstrip Management in the United States. International Journal of Wilderness, 5(2), 9-12.
  2. Meyer, S. S. (2000). Legislative Interpretation as a Guiding Tool for Wilderness Management. In: Cole, D. N., McCool, S. F., Borrie, W. T., & O'Laughlin, J., comps. Wilderness Science in a Time of Change Conference, Vol. 5: Wilderness Ecosystems, Threats, and Management; May 23-27, 1999; Missoula, MT. RMRS-P-15-Vol-5. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station Proceedings, pp. 343-47. Retrieved on February 3, 2010.
  3. U.S. Congress. Senate. Committee on Energy and Natural Resources. Endangered American Wilderness Act of 1977. S. Rept. 95-490 on H.R. 3454. 95th Cong. 1st sess. October 11, 1977.