Leg. History


The State Library of Arizona provides this website for informational purposes only and it is not intended as legal advice. This website is provided as a service, but may not be comprehensive. Since laws change over time, the sources offered may not represent the current state of the law. For more in-depth assistance, please consult legal counsel regarding your specific situation.


Why do I want to know the “Legislative History” of a law?

Are you trying to find out the meaning of a federal law?   You may need to know its “Legislative History”: the committee meetings, changes to the law’s wording (aka amendments), votes for and against, plus the arguments by members of Congress trying to pass or defeat it.

How do I start?

Understand how the bill became law and the legislative process.

To see what resources for you are created at each stage of the legislative process, view the University of Texas Tarlton Law Library’s chart.

      Good resources for understanding the legislative process include:

      • The easy and simple Ben’s Guide: How Laws are Made (from the U.S. Government Printing Office)
      • The Library of Congress has an overview on THOMAS  with more discussion

Also, ask yourself what you know about this piece of legislation already?

Do you have a US Code citation (42 U.S.C. 18001)?
A Public Law number (P.L. 111-148)
A Statute at Large citation? (124 Stat. 119 )
A bill number? (H.R. 3590)
Or the law’s title? (i.e. Patient Protection and Affordable Care Act)

These citations all relate to the same Act.

Having this information can help you find:

      1. The Bill or Act in different stages (introduced, engrossed, and sent to the President)
      2. Hearings: (these includes the statements of Witnesses and exhibits submitted)
      3. Committee Prints: These are research reports prepared by the committees’ staffmembers, the Library of Congress, or others.
      4. House or Senate Documents (type of document varies)
      5. Committee Reports: these help to explain the intent of the legislaion as it discusses the bill and its backgrounds, plus committee findings and other information.
      6. Debates (Discussions on the floor of Congress)
      7. Presidential Messages: look for signing statements or veto messages

Note: if you know the name of the Act or its public law number, we can help you check to see if a legislative history already exists.

One easy way to find alternate citations is the Cornell Law School’s Legal Information Institute’s Table of Popular Names

Need a complete guide to doing federal legislative history?
Try the Congressional Research Service’s guide.


Visit the Arizona Legislature’s students’ page  to see how a bill becomes a law in the state of Arizona.

The State Library has a Guide to finding Arizona Legislative History at our state Capitol.