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Pritzker Legal Research Center

Center on Wrongful Convictions (CWC) Research Guide

This guide supports the research needs of Northwestern Pritzker School of Law's Center on Wrongful Convictions (CWC)


Determine the Appropriate Statute to be Researched

To trace the legislative history of an Illinois statute it is necessary to obtain a copy of the statute and determine the particular Illinois public act that was the source for the section that you want to research. Illinois has multiple compilations, such as Smith-Hurd's Illinois Compiled Statutes Annotated (West) or the Illinois Compiled Statutes (Lexis). 

The Illinois Compiled Statutes are freely available at the Illinois General Assembly's website.

Having obtained the statute citation, it is a simple matter to find the statute. You need only locate the volume which includes the cited chapter and then find the correct section numbers.

House and Senate Debates; Importance of Bill Number in the Process

Once you have a copy of the statute, you are ready to begin your search for the legislative history. Although in the federal system committee reports and hearings provide a major source of legislative history, in Illinois these sources are mostly non-existent. Rather, the major source of legislative history is the floor debates.

In order to gain access to the debates, you must have the bill number of the statute. There are two methods for obtaining the bill number. First, at the end of each code section or paragraph is the effective date and a public act number, which is abbreviated P.A. The first two digits after the P.A. indicate the General Assembly number. That number can be used to locate the statute in Laws of the State of Illinois, which is arranged chronologically by the General Assembly and public act number. In individual volumes, right below the title of the public act is the bill number. For example, House bills will have an HB number and Senate bills will have an SB number.

The Laws of the State of Illinois volumes are located in the State Documents section on the third floor (S,IL KFI 1225 .A212). Online, Illinois public acts are available on HeinOnline, and freely available (from the 90th General Assembly forward) on the General Assembly's website.

The bill number can also be obtained through the Legislative Synopsis and Digest published by the Illinois Legislative Reference Bureau. Look at the Public Act Number. The first two digits represent the number of the General Assembly that enacted the bill. There are usually two or three volumes of the Legislative Synopsis and Digest for each General Assembly. At the end of the last volume for each Assembly is a subject index. You can look up the statute by subject to find the bill number. The disadvantage of this method is that finding the statute in the index may involve guessing a number of subject headings until you find the right one. Another approach is to use your statute citation and check the "Statutes Amended" section of the Digest which will also list the bill numbers associated with a statutory change.

Related bills or companion bills may also be worth pursuing in a legislative history. Comparing the enacted language with the language that was found in various versions of the bill which were not accepted can sometimes be used to infer the intent of the final version. The subject index in the Legislative Synopsis and Digest is also a good source for enumerating all of the bills that were introduced on a particular topic.

The Legislative Synopsis and Digest from the 92nd General Assembly (2001) + can be found via the LRB Digest on Volumes covering 1985 - 2005 are available online from the University of Illinois at Urbana-Champaign. Earlier volumes are available in print on the 2nd floor of the library in the Illinois State Documents section(S,IL KFI 1207 .L43). 

The text of House and Senate bills are available in microfiche (M,MFC KFI 1206 .I43, M,MFC KFI 1206 .I47), arranged by the number of the General Assembly. The headers on the top edge of each fiche give the first and last bill number on that fiche. The text of amendments to the bills is printed in the Illinois House and Senate Journals (S,IL KFI 1218.I47, S,IL KFI 1218.I43) on the day in which the amendment was proposed. Beginning with the 90th General Assembly (1997-1998), the full text of Illinois bills is available on the Illinois General Assembly web site (from the General Assembly page, under "Legislation and Laws"). 

The Legislative Synopsis and Digest provides a chronology of all action on each bill by each chamber of the General Assembly. Using the bill number, locate the summary of amendments and the chronology of legislative action. These lists will give you an idea of which debates you are interested in looking at. Beginning with the 90th General Assembly (1997-1998), the Illinois General Assembly web site has a "status table" for Illinois bills (under the "Bills and Resolutions" section). 

Text of the House and Senate Debates

Legislators have an opportunity to comment on a bill during the second and third reading. The debates contain a transcript of what is said on the floor of the House or Senate and are the primary source for substantive discussion of the intent of the legislature. Beginning with the 77th General Assembly (1971-1972) the House Debates are available on the Illinois General Assembly web site (Select "Transcripts"). Beginning with the 77th General Assembly (1971-1972), the Senate Debates are also available on the Illinois General Assembly web site (select "Transcripts"). There are not transcripts available for legislation passed prior to the 77th General Assembly.

For legislation pre-dating the 77th General Assembly, some legislative history might be gleaned from newspaper accounts of the legislation's passage.  Generally, the best sources for newspaper accounts are the State Journal-Register (Springfield) and the Chicago Tribune.

Committee Hearings and Reports

Since the mid-1970s, House Committee meetings have been recorded on audio tapes. Individual tapes may be ordered by calling the House Transcribing Clerk at (217) 782-8100. To order these tapes by phone it is necessary to provide bill number and General Assembly number or a Public Act number. References to committee reports appear in the Illinois House or Senate Journals and can be located by checking the "Record of Bills" section in the last volume of the respective volume of the Illinois House or Senate Journals and checking under the column "Report of Committee" and "Other Proceedings." (However, these reports are often brief and of little substantive value and report only the committee vote.)

Governor's Actions

The Governor can affect how a law is implemented through the use of the approval statement, amendatory veto, or the veto message. These documents are located in the House or Senate Journal. In the last volume (of the appropriate year) check the "Index of Subjects" under the heading "Governor." Beginning with the 77th General Assembly (1971-1972), the House and Senate Journals are available on the Illinois General Assembly web site (select "Journals" under either the House or the Senate, whichever is appropriate).

In addition, Westlaw also allows the researcher to retrieve all of the available legislative documents for an Illinois legislative history. This includes bill statuses, House and Senate floor transcripts and Illinois House and Senate Journals. Simply pull up your statutory section in Westlaw and click on the "History" tab near the top to see the available legislative history.

Public Acts

The Illinois General Assembly provides the texts of Illinois Public Acts from the 90th General Assembly (1997-1998).  HeinOnline's Session Laws library has all Illinois Public Acts dating back to the establishment of the Illinois Territory in 1809.