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Missouri Criminal Law - Process, Issues, and Research: Introduction


The field of criminal law is one in which many lawyers will find themselves practicing, at least to some degree, at some point in their careers, especially if they were in a small firm in general practice. However, criminal law plays by its own rules. In order for an attorney to act as an effective advocate in a criminal proceeding, she must be able to understand how the criminal justice system operates from a procedural perspective, while also understanding the complexities that might arise in a situation involving a potential violation of criminal law. Unfortunately, basic law school courses in criminal law often fail to provide the necessary background in order to effectively navigate the criminal justice system and advocate for a client. Even newly hired Public Defenders or local prosecutors often enter their jobs with little refined understanding of the system in which they will be working. This research guide’s purpose is to provide a basic introduction to the criminal justice process in Missouri, while also providing an attorney new to the field with recommendations and tools for approaching a criminal case.


This guide focuses on two areas of importance to attorneys new to the field of criminal law: the criminal justice process, and the interpretation of criminal statutes and their application to the facts of a case.

The guide’s goal is to provide the tools necessary to enable an attorney to effectively navigate a criminal case. To that end, it provides a number of primary and secondary sources that will assist an attorney in their research process. It also provides directions to access sample forms that may be useful during the course of criminal proceedings.

While many of the basic strategies discussed in this guide may be effective in other states, this guide is limited in scope to discussing Missouri criminal law and the sources needed to effectively represent a party in a criminal proceeding.

To allow the user to practice utilizing the tools discussed in this guide, some hypothetical problems are provided.

Beginning the Research Process

If you are a private defense attorney, a family member of a potential client may have just come into your office to tell their story and ask you to represent their loved one. If you are a Public Defender, you will probably meet your potential client only when your client is going to be arraigned in court and they apply for Public Defender representation. If you are a prosecutor, you were probably assigned a case and provided the file with relevant documents from the police indicating the suggested charges and the facts supporting the charge.

No matter how you came about the case, you will have to begin by looking at the facts and the statutes. Criminal law is derived from statutes. In order to understand how to approach any given case, the attorney needs to understand the statute that establishes the alleged conduct as being prohibited. Most of this guide is dedicated to providing the attorney with the tools necessary to enable the attorney to effectively analyze what the statute requires, what the courts require based on that statute, and how to determine whether the facts of the case meet those requirements.

Sample Documents and Forms

A number of documents must be filed with the court during the course of a criminal proceeding. Documents such as waivers, motions, notice, and others must all be filed, and the form they take change with the situation. Fortunately, sample versions of the forms utilized in Missouri criminal practice can be found in secondary sources. While this guide will not provide a comprehensive examination of these documents, it will direct the reader to the relevant sources that provide these documents.

Change is Coming

The Missouri Legislature recently passed a complete overhaul of Missouri’s criminal code. The changes made to the code will take effect in January 2017. These changes should not effect the information provided in this guide, insofar as the information is substantively accurate.

For the past few years, there have been efforts by the Missouri Bar Criminal Law Committee to revise the Missouri Criminal Code. Among the goals of the revisions were to place all of the criminal statutory provisions into a single area of the Revised Statutes of Missouri. Currently, some offenses, such as those involving drugs, are in Chapter 195, while the vast majority of the criminal code is located in Chapter 556-578. Drug offenses are being moved into an entirely new chapter, Chapter 579.

There was also some concern about consolidating the statutes in order to make them more efficient. For example, there are currently more than 25 separate assault offenses. The revisions will establish 4 assault offenses and 4 domestic assault offenses, while providing for enhancement of penalties based on circumstances such as “special victims” (i.e. law enforcement, etc.).

The revisions also modify the sentencing structure for criminal offenses, establishing a new class of felony in order to create more effective ranges of punishment for various offenses.


It is very important that the attorney practicing criminal law understand how to navigate the research process and find the information needed to do the job effectively. The failure to research an issue may result in an innocent person being imprisoned, or a guilty person going free. When liberty and safety are on the line, the attorneys representing each side must be able to research issues effectively.

Criminal law courses in law school prepare the attorney to understand how courts think about issues in criminal law. They help the student understand how elements are determined, and how they are interpreted. They help the student learn to apply facts to those elements. However, they often do not provide the student with the tools necessary to take on a criminal case directly, where the facts are rarely so neat, and the crimes are often less clearly defined. This guide should help the attorney new to the field begin to understand what factors they must consider as they begin their research process, and where they must look in order to better understand how those factors influence a case.

The tabs along the top of the page direct the user to the information discussed within. To practice using this guide, consult the tab labeled “Research Questions.” Nulla poena sine lege.

Student Guide Author

Jared Guemmer will graduate from the University of Missouri School of Law in May 2016. As of the time of this guide’s creation, Jared was an Associate Member of the Missouri Law Review.

This guide was originally created in support of Professor Diamond's Advanced Legal Research class. The contents of this guide should not be taken as legal advice or as the work product of MU Law librarians.

Accessibility of Sources

Those working for the Public Defender or for a prosecutor will have few concerns about access to sources. Those agencies provide access to almost any legal resource the attorney will need to be able to do her job.

For the private attorney, access to legal sources is rarely cheap. Most research will involve case law, meaning access to databases like Westlaw, Lexis, FastCase, or Bloomberg Law will be necessary. However, access to the relevant secondary sources is not typically part of the base subscription for any of these services. The good news for private attorneys entering the field of criminal law is that all of the important secondary sources can be accessed for free in a local courthouse. Every courthouse in Missouri has its own law library, and those libraries will be able to provide access to print or electronic versions of the secondary sources.