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Summer Legal Research Tips: Illinois Case Law

Illinois Courts Quick Links

Is This Case Still Good?

Case law is always changing over time as other courts interpret and comment upon earlier decisions. One of the key steps in doing case law research is determining whether a particular case is still applicable to a certain situation.

Lexis Academic provides a way for researchers to check the status of a particular decision. After opening Lexis Academic, choose "US Legal" from the side menu, and then select "Shepard's Citations". With this tool, a researcher can enter a case citation and get a report that shows the history of that particular case as well as a list of other cases that discuss the citation entered.

Google Scholar also provides citation reports for the cases it covers.

Introduction to Illinois Courts

The Illinois court system is composed of three basic levels:

Illinois Supreme Court The Supreme Court is at the top of the Illinois court food chain and is the last court of appeal in the Illinois system. The Supreme Court hears certain appeals from the Circuit Courts and the Appellate Courts, as well as reviews of death sentences.
Illinois District Courts The District Courts are the first level of appeal in the Illinois system. There are 5 appellate districts in Illinois, and these courts hear appeals from the Circuit Courts. These courts may also review decisions from administrative agencies.
Illinois Circuit Courts These are the trial level courts of the Illinois system. There are 23 circuit courts in Illinois, each covering 1 to 12 counties. Circuit courts handle trials and local issues and in some cases may review decisions of administrative agencies. 


There are also other parts of the Illinois system that deal with special issues, such as arbitration panels in certain counties that review lawsuits under a certain dollar amount. The Illinois Courts website has a good explanation of how a case moves through the Illinois court system.

How to Cite Illinois Cases

The Illinois Supreme Court has adopted a new form of public domain citation.  It is based on docket numbers and paragraphs rather than volumes and page numbers.


An example of a Supreme Court citation under the new system would look like this: People v Doe, 2011 IL 102345, ¶15. This shows the name of the case, 2011 as the year of decision, the Illinois Supreme Court as the court of decision, 102345 as the court-assigned identifier number which is the docket number of the case and a pinpoint reference to the 15th paragraph in the opinion.

An example of an Appellate Court decision from the Third Judicial District would look like this: People v. Doe, 2011 IL App (3d), 101234, ¶15. In the Appellate Court, the unique identifier number would consist of the last six digits of the docket number.

Unpublished orders filed under Supreme Court Rule 23 will have the letter “U” appended to the unique-identifier number. Rule 23 orders will still be posted to the Court’s web site.

How to Find Illinois Case Law

The main database for researching Illinois case law is Lexis Academic. After opening Lexis, choose "US Legal" from the side menu and then choose "Federal & State Cases".

On that page, set the jurisdiction to "Illinois".

Lexis Academic can be searched by citation, by party name, by legal topic, by judges, attorneys, or by keyword. You can also narrow the results by date.

Aside from Lexis Academic, there are other sources of Illinois law available online: