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Criminal Law
University of Kentucky School of Law
Welling, Sarah N.

Crim. Law


Fall 2015

I. Basic Criminal Law Doctrines

A. Background

There are four recognized legitimate purposes for punishment under the criminal law:

Retribution: Punishment is related to the personal culpability of the defendant.
Deterrence: Certain and harsh punishment will deter people from committing bad acts.
Incapacitation: Punishment is designed to keep a criminal from committing future acts when it is determined that they are not susceptible to deterrence.
Rehabilitation: Punishment is designed to “heal” the criminal actor. This purpose forms the basis for the parole system.

Criminal liability (Crime) has two distinct elements:

Conduct Requirement (actus reus)
Mental State Requirement (mens rea)

B. Introduction to the Mens Rea

Courts have systematically held that, except for a very limited number of strict liability crimes, criminal liability requires the actor to have a certain mental state.
Model Penal Code

Purposely/Intentionally: It is the actor’s conscious objective to engage in criminal conduct or cause the criminal result.
Knowingly: The actor is aware that his conduct is criminal and he is aware the criminal result is practically certain to occur.
Recklessly: The actor consciously disregards a substantial and unjustifiable risk that his conduct will result in a criminal act and that result occurs.

The act must be a gross deviation from the standard of conduct a law-abiding citizen would observe in the actor’s position.

Negligently: The actor should be aware of a substantial and unjustifiable risk that his conduct will result in a criminal act, but is not aware of the risk and his actions bring about the criminal result.

The act must involve a gross deviation from the standard of care a reasonable person would observe in the actor’s situation.

When a crime requires a mens rea, the mens reas which rank higher on the list from the one required are also included in mens reas that could establish the crime. For example: if a law requires a negligent mens rea, then it could also be satisfied with a reckless, knowingly, or intentional mens rea.
Knowledge can be established when a purpose is aware of a high probability that a criminal act is occurring, but does nothing to discover it.

MPC version of “wilful blindness” established in the common law

Common Law

The mens rea of ‘knowingly’ can also be proven through “willful blindness”

Willful blindness describes when the actor has suspicion of an illegal act occurring, but deliberately avoids that suspicion so as not to discover or know about the illegal act.

“One who does not possess positive knowledge only because he consciously avoided it.”
Willful blindness is a step above recklessness or negligence, because for WB an actor must take deliberate steps to avoid confirming their suspicions of criminality. A reckless actor knew of a substantial risk for criminal activity to occur from his actions, but did them anyways and a negligent defendant should have known of such a risk.
Some have argued this mens rea imposes a duty of investigation onto the actor.

Having a “reason to believe” something may be criminal has been defined as negligence.
Having a “reason to know” something in criminal has been defined as recklessness.

C. Overview of the Sources of Criminal Law

Criminal liability requires a statute. If there is no statute making specific conduct criminal, it is not.
There are three areas that criminal law generally is derived from and which form the basis for statutes:

Common Law: this is the law which was adopted in England and carried over to the American Legal System. It contains a mixture of court made and statute defined criminal acts and defenses. While today, all criminal acts are defined by statute, many of these statutes are based on traditional common law crimes.
Model Penal Code: the American Law Institute formed the MPC in 1962 as a result of their view that common law in the United States was full of confusion. The MPC sought to eliminate much of that confusion. The MPC itself is not a statute, but it has been adopted in various parts by many jurisdictions across the United States and forms the basis for current statutes in those jurisdictions.
Federal Criminal Law: while most of the criminal law is left to the states and based on the traditional common law or more modern MPC, the federal government has its own set of criminal law statutes. The federal criminal law exists independently from the state criminal laws and is enforced only in federal courts.

D. Intoxication as a Defense

Common Law

Early American Law said intoxication was never a justification or excuse for committing a crime.
Eventually the common law developed to allow intoxication as a possible defense to negate the mental state requirement of a crime. Intoxication was allowed to negate a mental state requirement of specific intent, but not general intent.

Model Penal Code

The MPC took the approach that intoxication is never an affirmative defense, but can only be used to negate a certain element of the crime.
The MPC also went on to say that intoxication could never negate crimes which required a mental state of recklessness or negligence.

Courts have ruled that intoxication is not a fundamental defense to American law and not required under

Lack of knowledge about a law is a defense if the law has not been published or otherwise reasonably made available.

In the modern era where laws are constantly published, this is just theoretical example that provides no practical application.

Lack of knowledge may also be a defense where the actor acts in reasonable reliance on an official statement of the law which is later determined to be invalid.

Such official statement can be a statute, judicial decision, administrative order, or official interpretation.
An example of this defense is provided in the case of the CIA actors who illegally tortured terrorist detainees after September 11th. These actors were acting under an official interpretation of the torture statutes provided by the Justice Department’s Office of Legal Counsel where they defined certain techniques being used as not torture.

The legislature can write a ‘knowledge of the law’ requirement into a statute. The word willfully is generally used when the legislature wants to include such a requirement.

G. Strict Liability Crimes

Strict liability crimes are ones which require no mens rea. Unlike the majority of crimes where the statute either requires a specific mens rea or the courts have interpreted one, these crimes allow liability to attach even where the defendant had no mens rea. This means that the defenses which are able to negate certain mens reas are not effective against strict liability offenses. (Defenses such as intoxication, mistake of fact, etc.)
Common Law

No strict liability crimes derived from the common law
The Supreme Court has said only crimes which have no moral condemnation and where the penalty is very low can be strict liability crimes.
New public welfare laws may be strict liability
When assessing whether a statute can be a strict liability crime the court looks at a number of factors from Morissette:

How high is the penalty
How stigmatizing is the crime
Does the crime have a long common law history

Statutory rape is defined as a strict liability crime, but it is an outlier and does not fall into the usual paradigm for when strict liability attaches.