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Federal Legislative History: Legislative History Research Process


Online subscription and government resources continue to improve the process of identifying and locating legislative history documents related to particular legislation.  ProQuest Legislative Insight and ProQuest Congressional,, Lexis, Westlaw, HeinOnline, and offer federal legislative history materials.  ProQuest Legislative Insight and ProQuest Congressional are the most comprehensive of the online resources and should be the first stop in a legislative history search.  Official versions of source documents, in PDF format, are available in these databases.  For older materials (early-mid 20c and before), HeinOnline is recommended.  However, some older documents reside in the ProQuest databases, especially if they relate to subsequent, successfully enacted legislation. 

Federal Legislative History Steps

Step 1.  Identify the public law(s).  The language of each United States Code provision is based not only on the original act that created it, but also on the later laws that amended it.  To compile a complete legislative history for a current federal law, it is necessary to locate the documents related to both the creating act and its later amendments.  However, it is more likely that research will be conducted to ascertain the Congressional intent for a specific phrase, term or subsection within a statutory provision.  In that case, the first step is to identify the public law whether it is the original act or later amendment that created the ambiguous phrase, term or subsection. 

The history notes section, located after the text of the statute, will list the public law numbers for the original act and the later acts amending the statute.  To compile a complete legislative history, it is necessary to note each of the public law numbers in the history notes and research each of those laws.  Otherwise, it is necessary to determine which of the public laws listed in the history notes created the portion of the statutory language that is the subject of the research.  Sometimes the history notes summarize the changes made by each of the public laws and the information in the summaries may be all that is needed to identify the correct public law.  If not, the researcher should read the public laws listed, starting with the original enactment, until the public law creating the subject statutory language is found. 

ProQuest Legislative Insight and ProQuest Congressional are the most comprehensive of the online resources available and should be the first sources you consult in a legislative history search. Term searching and citation searching are available.

Public laws are reprinted in chronological order in the Statutes at Large and USCCAN.  The Statutes at Large, or session laws, contains the official full text version of each public law passed during a session of Congress.  USCCAN (or United States Code Congressional and Administrative News) contains the unofficial full text version of the public laws along with some legislative history information that is discussed later in this guide.  The Statutes at Large can be found in print in the library (KF50.U52) and online on HeinOnline and  USCCAN can be found in print in the library (KF51.U49) and on Westlaw.  Public laws are also available in Lexis and Westlaw.

Step 2.  Gather information about the public law(s).  While it is increasingly easier to find material using only a public law number, much of the documentation will be indexed around the Statutes at Large citation and the bill number.   Bill numbers will be published in the session laws, and for recent public laws, on the slip laws themselves.  The public law number, the Statutes at Large citation, and the bill number should be assembled for your research.

Step 3.  Search for compiled legislative histories or individual documents about the public law(s).  Considerable research time can be saved if a legislative history has already been compiled for the law in question. Sometimes the compiled legislative history will reprint the text of all of the documents generated during the legislative process and the researcher's work will be done.  Other times, the compiled legislative history will be a list of citations to bills, reports, hearings and floor debates and then the researcher will have to locate the text of those documents using the resources listed in this guide. Compiled legislative histories and lists of citations may exist for selected laws, either compiled  by a previous researcher or issued on a regular continuing basis by commercial sources. Compiled legislative histories are available in legislative history bibliographies, through subject treatises and texts, and on Lexis and Westlaw. A good way to find a compiled legislative history is via ProQuest Legislative Insight.  Citations to individual documents are available on ProQuest Congressional.  HeinOnline is another excellent source. The Compiled Legislative Histories tab in this guide provides more information on source identification and access. 

Due to constraints on time and money, or the nature of a research project, a full legislative history may not be desired or necessary.  A cursory search for a compiled legislative history may be sufficient, or this step might be skipped altogether and a search run for only the most authoritative sources of Congressional intent, like committee reports. 

Step 4.  Identify and locate legislative history documents related to the public law(s).  If the search for a compiled legislative history was unsuccessful or one is not needed, the next step is to identify and locate some or all of the documents created during the legislative process for the public law. 

When researching recent laws, online resources have greatly simplified the process of identifying and locating federal legislative history documents related to particular legislation.  ProQuest Legislative Insight and ProQuest Congressional, Lexis, Westlaw, HeinOnline, and offer legislative history materials. 

The law library has the print Congressional Information Service (CIS) volumes for 1970-2015. (Z1223.A2 C56 in Reference) In print, the Congressional Information Service (CIS) volumes offer indexing and abstracting of legislative materials.  A reference librarian can assist patrons using this resource. The documents pages in this guide (bills, hearings, reports, floor debates and other) detail specifically where and how to find the full documents.  However, ProQuest Congressional and ProQuest Legislative Insight, available from the library home page, are the preferred resources. Along with HeinOnline, the ProQuest databases are the most comprehensive option and offer subject and keyword searching, PDF documents, etc. 

Step 5.  Review the selected documents.  The final step is to study the documents and determine whether they clear up the ambiguity existing in the statutory language. If a court considers legislative history, certain documents, e.g., committee reports, may be viewed as more authoritative than other parts of the history, e.g., floor testimony published in the Congressional Record.


Some words of caution regarding the use of legislative history:

  1. Legislative history is only persuasive authority, usually turned to as a last resort.  Analyze the text of the statute in its entirety. Read all the case law that interprets the statute, and consider relevant regulations before turning to the legislative history of a statute to solve a research problem.
  2. Some judges and practitioners will be more receptive to using legislative history as a statutory construction tool than others. Justice Breyer authored a law review article exploring the use of legislative history.  While he defends its use, he does explain the criticisms of legislative history as well. See, On the Uses of Legislative History in Interpreting Statutes, 65 S. Cal. L. Rev. 845 (1991-1992). (HeinOnline)
  3. Legislative history usually does not conclusively resolve questions of interpretation and application.  While the legislative history of a statute may offer some information on its origins and the policy supporting its enactment, it is unlikely to contain discussions of how a statute would apply to highly specific fact situations.  Further, legislative history documents may be contradictory, with one document supporting one interpretation of a statute and another document supporting the alternative interpretation.
  4. Legislative history research can be very tedious and time-consuming.  Law clerks, associates, and research assistants should make sure that legislative history is desired from the assigning judge, attorney, or professor before embarking on legislative history research.
  5. Some documents are considered more valuable than others in a statutory construction argument based on legislative history.  For example, an argument based on a committee report might be given more weight than a hearing transcript.  

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