The Model Penal Code
The Model Penal Code (MPC) and its commentary were promulgated by the American Law Institute in 1962, drafted in the 1950s. The purpose and "dream" of the draft was to clearly state those penal provisions which should be uniform throughout the United States, to adequately deal with those modern situations not adequately covered by the common law and to broadly restate those common law penal provisions which should be uniform throughout the United States.
For those interested in the MPC itself , the American Law Institute provides these links:
The Model Penal Code (Crimes) – Uniform Laws
The Model Penal Code (Crimes) – Criminal Procedure
The Model Penal Code: A Brief History – American Law Institute
The Model Penal Code: An Overview – American Law Institute
Common Law
Common law, as a concept, has evolved from various sources and teachings of his time. In England, the common law originates from medieval times and was intended to move away from time-consuming royal judgments. Common law began to develop into the 13th century and has become part of the American legal system largely through its storied history in the United States in the Colonial period and after achieving independence. The Anglo-American common law system is based primarily on the concept of stare decisis, or deference to the decisions of past judges. Under the concept of stare decisis, a judge will decide a case before him or her based largely with consideration given to prior court decisions in similar cases. As such, common law is considered to be case law, in that it relies heavily on judicial decisions as a main source of authority rather than legislative statutes or codified regulations. The concept of common law serves to increase the stability of legal systems while also allowing for an adaptable approach to otherwise vague laws by allowing courts to explain and, as necessary, add to the statutes through their decisions.
Differences Between The Model Penal Code and Common Law
The Model Penal Code (MPC) and common law both have their own unique approaches to defining crimes. The MPC is much more exhaustive in its definitions than the common law. Additionally, the MPC tends to define crimes more narrowly. For example, some things that are considered a crime under common law are not defined as crimes by the MPC. Slander is one example of this. Slander is defined in the MPC, but only in relationship to defamation liability, not as a crime.
The MPC also groups crimes into four categories: felonies, misdemeanors, petty misdemeanors and violations. The key distinction between felonies and misdemeanors involves who charges the crime (a district attorney for felonies; a city or county police department for misdemeanors). As you can see, these differences are more administrative than substantive.
Not only do the MPC and common law differ in their definitions of crimes, they also differ in how they define the penalties for each crime. Again, the MPC groups offenses into felonies and misdemeanors, whereas common law does not generally categorize crimes.
Lastly, the two also vary in how they interpret crimes. Common law is fairly inflexible in its interpretation. Once a criminal code is established it is difficult to change, even if offenses become outdated. The MPC adopts a more natural and specific interpretation of criminal law: by reading new offenses into a criminal code and striking old ones that are no longer relevant.
Model Penal Code vs Common Law Comparison Chart
MODEL PENAL CODE
COMMON LAW
Definitions
Elements: The conduct, the result, and the mens rea.
Scope of Application: Applies to all offenses within its jurisdiction.
Mens Rea
General Intent: "No person shall be found guilty…unless he acted purposely, knowingly, recklessly, or negligently with respect to each material element of the offense."U.S. v. Martinez, 633 F.2d 760,764 (2nd Cir 1980).
Specific Intent: For crime with "purposeful or knowing" mens reaprovisions, MPC section 1.13(9) provides that "unless a contrary purpose plainly appears, the terms ‘purposely’, ‘knowingly,’ and ‘recklessly’, and ‘criminal negligence’ shall each apply also to the corresponding conduct [or] result or attendant circumstances element of the same or an equivalent provision of any statute defining an offense if nothing in such statute otherwise prohibits the applicability of such terms to such element."
Moreover , no presumption concerning culpability is to be drawn:
(1) …from the fact that a definition of an offense only specifies a particular kind of culpability with respect to a material element of the offense;..
(3) …the requirement that the element of culpability be established, except in a very limited class of offenses, is applicable to each material element of the conduct described by the statute defining the offense … and not only to those designated as a "mental state."
U.S. v. Blackerby, 394 F. Supp. 2d 1169, 1178-79 (D. Alaska 2005)(citing Model Penal Code § 2.02(3) and (9)).
Distinct: Common law jurisdiction may or may not provide for a specific mens rea.
Strict Liability: MPC does not allow strict liability.
Common Law Key
Crimes w/o Mens Rea (Traditionally): Strict Liability (traditionally); Liability Without Fault (modern trend in common law)
Legislative Intent: Statutory
Evidentiary Presumption
Proof of any instants of mens rea presumed (burden of proof on defendant): Mens Rea not required; State does not need to prove mens reain order to obtain conviction.
Malcolm v. State, 301 P.2d 775 (1956).
Modern Jurisdiction Application
The influence of the Model Penal Code on modern law is expansive. Most jurisdictions around the United States have based some or all of their penal codes on it. Still, in these jurisdictions, the MPC is not the sole authority on how crimes are charged or tried.
Many states just outright adopted the MPC itself. Ohio is one state that has. Because its code is similar to the MPC, many states with less comprehensive criminal codes look to it for guidance on certain legal issues and questions. New York went about adopting the MPC piecemeal. Its Penal Law includes offenses, principles, and defenses taken from the Model Penal Code, while keeping its common law roots in some other areas. California, however, codified most of the MPC except for its provisions on liability for group conduct. In these jurisdictions, the MPC is often treated as the primary source of law about criminal offenses.
Some states are organized around particular sections of the MPC, but haven’t adopted the entirety of the code. Mississippi, for example, took the final Sections of the MPC and used them as a rough foundation to build its own code. There are many areas where it relies heavily on common law principles, so it is not entirely based on the Model Penal Code. Other states like Michigan incorporate various provisions of the MPC into their Penal Code. Though they have adopted many of its provisions, they do not consider it to be their primary source of law.
Some jurisdictions have credits their practice to the "MPC" but were not involved in its development. They have simply adopted certain sections or principles, and have had courts apply them in practice. Illinois is one state that does this. Vermont does something quite similar by relying heavily on common law while considering select sections of the MPC to be persuasive in their case law.
The influence of the Model Penal Code still reaches states that have not formally adopted any part of it. Many courts will consider the Model Penal Code as persuasive when evaluating various aspects of common law.
Impact on Reforms
The Model Penal Code’s clear structure and modern terminology have continued to influence the development of criminal law across many states. As of today, it is estimated that over two-thirds of state legislatures have enacted new statutes that more closely resemble proportional criminal codes (for example, integration of sentencing guidelines into a single statute.) Many states have borrowed heavily from the MPC in their reform efforts. Most notably, Washington (post-early 1960s), Kansas, and North Carolina have each enacted their own reforms that largely mimic the principles of the MPC. Similarly, the American Law Institute’s (ALI) Model Penal Code Supplement was issued to reflect judicial developments and legislative enactments that occurred after the MPC’s original publication. This Supplement serves as a useful guide for new code legislation. Likewise, the ALI is involved in updating a new MPC3. While it has not been officially adopted by any states, the MPC3 is being used throughout legal academia and is often considered a major work of scholarship. Similarly , many foreign jurisdictions have adopted criminal codes that stress objectives similar to that of the MPC and other similar criminal codes. For example, both of Canada’s national and provincial criminal codes were heavily influenced by MPC principles. There has also been an ongoing international movement towards MPC-influenced codes. A few examples include codifications issued in China, Switzerland, Israel, Germany, Japan, Netherlands, Queensland, and Korea. Due to the MPC’s emphasis on the difference between a substantive offense and a related grade of culpability, several key United States court cases have continued to shift the way in which the country views the meaning of specific offenses. For instance, in State v. Larocco (2004), the state supreme court overruled previous cases that upheld the distinction between reckless and negligent homicide. Similarly, CP § 1.04(5) (2012) distinguishes between the definitions of careless, negligent, grossly negligent, and reckless conduct. Pennsylvania’s high court approved this distinction as crucial for determining the appropriate level of culpability for a specific offense.