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Case Law Guide

Decisions by courts are referred to as cases, case law or opinions 

Court Structure

There are generally three levels in a court system:

  • Trial Courts (Courts of First Instance) are the first level.  Trial courts make determinations of law and fact in both civil and criminal cases.  Juries are generally involved in these cases.
  • Circuit Courts (Courts of Appeal) are the second level.  Appellate courts examine cases for errors in the law in the records of the lower courts.  Decisions are made by judges, no juries are involved.
  • Supreme Court (Court of Last Resort) is the highest appeals court.  A loser in an appellate court case can appeal the case to the Supreme Court. The Supreme Court decides which cases it will hear.  It can refuse to hear a case if they feel it is without merit.

Federal and State Jurisdictions 

Determining whether a case involves a federal or state law is not always easy.  Below are some examples of types of cases that are considered at each level:

State:  Each of the 50 states has its own court legal system.  While there are some similarities between them, each has its own constitution, which creates a distinct system of government.  Most issues affecting day-to-day life are governed by state law.  Major areas include: domestic relations (marriage and divorce, parental rights, custody of children); property law (real estate inheritance, landlord-tenant relation); commercial law; criminal law.

Federal: The Constitution of the United States limits the power of the federal government to specific areas. These include admiralty, bankruptcy, copyright, and immigration.  Other areas that Congress has determined have overriding national concern are consumer protection, environmental law, and labor relations, so these issues also fall under federal jurisdiction.

Key Terms

Reporter:  A Reporter is a collection of court decisions for a particular court or group of courts. 

Digest:  A Digest is used to locate cases on a particular subject. Digests provide summaries of and citations to cases, but do not provide access to the cases themselves. To gain access to an actual case, use the appropriate Reporter.

Slip Opinions: Before a case is put into a Reporter, it is first issued as a Slip Opinion. Slip Opinions look like pamphlets and do not have a Legal Citation attached to them. The Cofrin Library does not receive Slip Opinions for all courts.

Legal Citation: A legal citation is an abbreviated form of the location of a case.

Parallel Citations:;Are additional citations in the same entry that indicate that a case can also be found in another reporter series.

Pocket Part:  A Pocket Part is an update to a publication.  It is a pamphlet placed inside the back cover of the book.  (They are referred to as Pocket Parts, because generally there is a pocket in the back of the volume for the update to be placed inside).  Be sure to check for a pocket part in the book you are using to make sure you get the most up-to-date information available.

Key Numbering Systems:  There are two different types of key numbering systems.  West Publishing Co. uses the West Key Numbering System to organize its publications.  Lawyer's Cooperative Publishing uses a system called Total Client-Service Library to organize its cases.

  • The West Key Numbering System: breaks the law into 7 major classes, 400 legal topics (concepts) and over 100,000 subtopics, called key numbers. (A detailed explanation is available in West Analysis of American Law Ref GVP-WI 5.5:W47).  You will find West Key Numbering in West's Wisconsin Key Number Digest and West's United States Supreme Court Digest.

  • The Total Client-Service Library system organizes works into 400 broad topics which are further subdivided into narrower topics. Publications by Lawyer's Cooperative Publishing located in the Cofrin Library include: American Jurisprudence 2d and United States Code Service (USCS)

Searching for Legal Cases

Searching for a legal case is generally done one of two ways:

  • The first way is with a legal citation already in hand [e.g. Roe v. Wade 410 US 113 (1973)].  When you already have a citation, use the appropriate Reporter to find the case.
  • The second way is to research a specific topic to find appropriate legal citations.  For this you will generally begin with a Digest.

Understanding Legal Citations

Legal Citations are generally made up of five parts:

  • Name of the case (usually name vs. name)
  • Volume number where the case appears
  • Abbreviation of the title of the set of books reporting the case (Reporter)
  • Page number
  • Year

The example citation show above is Roe v. Wade 410 U.S. 114 (1973)

Example Citation
Roe v. Wade 410 U.S. 114 1973
Name Volume # Title  Page # Year

Note on Title Abbreviations:  Publications where the names of cases appear have standard abbreviations used throughout case law.  Some of the abbreviations you may run across in the Cofrin Library include:

Title Abbreviations
Am Jur 2nd American Jurisprudence 2nd Set Ref KF 154 .A42
US United States Reports Ref GVP US Ju 6.8/A
USC United States Code Ref GVP US Y 1.2/5-3x
USTC US Tax Cases Ref HJ 3251 .A39 C6
ELR Environmental Law Reporter Ref KF 3775 .A6 E5
Wis Wisconsin Reports Ref GVP Wis Cou.1 
Wis 2d Wisconsin Reports 2nd Series Ref GVP Wis Cou.1 2nd Ser.

 A complete Table of Abbreviations is available in the Black's Law Dictionary Ref KF 156 I56 B53 1990

Using Digests

If you want to locate cases on a particular subject, use a Digest.  Digests are arranged in alphabetical order by broad subject areas, which are subdivided into more specific subject areas.  A Table of Contents for a broad subject area (e.g. Adoption) is provided for assistance with more specific topics (e.g. Persons who may Adopt).  Digests provide summaries of and citations to cases, but do not provide access to the cases themselves.  To read the case itself, use the citation provided by the digest to find the case in the appropriate Reporter.

If you are not sure what broad legal topic may contain relevant cases on your subject, the detailed subject index to the digest, called the Descriptive Word Index, will be helpful.

The Cofrin Library has two major Digest sets but published by West Publishing Co.:

West Publishing Co Digest Sets United States Supreme Court Digest US Supreme Court Cases

Ref GVP US JU 6.8/X:

West's Wisconsin Key Number Digest WI Supreme Court Cases Ref GVP Wis Z. 5/5

Lexis Nexis Academic

In addition to the print Reporters and Digests available in the Cofrin Library, the Library also offers the database Lexis-Nexis Academic Universe that includes a comprehensive Legal Research section.  It allows access to court cases by topic or by case name and number, as well as access to law journals and reviews.

To access Lexis Nexis Academic connect to the How Do I Find Article page and select Lexis Nexis Academic from the Online Database drop-down menu.  Once you are in Academic Universe, click on Legal Research. 

Wisconsin State Law Library & Brown County Law Library

For complicated law reference questions, call the Wisconsin State Law Library toll-free number at: (800) 322-9755

The Brown County Courthouse Law Library is located at 100 S. Jefferson Street in Downtown Green Bay  (920) 448-4114. Note:This library is not staffed by a librarian. It is strictly a self-help environment.