The purpose of this guide is to describe the basic steps in the Illinois legislative process, and suggest sources available to Pritzker Legal Research Center patrons for the text of Illinois legislative documents. Increasingly the Internet is becoming the most up-to-date source for the text of Illinois legislative documents. This guide incorporates links to the web sites mentioned in the text.

Compiling a legislative history involves following the steps in the process by which a bill becomes a law (or, in some instances, the process by which a bill failed to become law), and examining the documents created during this process. Legislative history is sometimes used by courts as a means of statutory interpretation to find legislative intent if a statute is vague, ambiguous, contradictory, or the like. Legislative history is considered only persuasive legal authority. Courts consider the legislative history of a statute if there is some doubt about the meaning of specific language. However, if the text of an act contradicts a statement in the legislative history, the statutory language controls.  Courts generally will not resort to legislative history as a means of statutory construction if the meaning of the statute is plain on its face.