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Criminal Law
Rutgers University, Newark School of Law
Thomas, George C.


A. Nature of Criminal Law
B. Proving Guilt at Trial
a. Right to Trial by Jury
b. Burden of Proof
i. Presumption of Innocence
c. Jury Nullification

Principles of Criminal Punishment

A. Punishment and Criminal Law Theory
B. Punishment Defined
C. Theories of Punishment
a. Utilitarianism
b. Retributivism
c. Denunciation (Expressive Theory)
d. Mixed Theories
D. Sentencing

Principle of Legality

A. Previously Defined Conduct
a. No ex-post facto law, no person can be prosecuted for something that is not a crime
b. Where D harassed P with lewd and disturbing phone calls, court found him guilty of a broad common law violation about public morality. The dissent discusses that this loose interpretation and application is a violation of the principle of legality. (Commonwealth v. Mochan, 1955)
c. Where a man killed a viable fetus in a woman and the murder law was from the 1800s, the court had to interpret the meaning of “human being” as it was in the 1800’s (a baby that had been born alive) but urged the legislature to update the law, which it later did. (Keeler v. Superior Court)
B. Statutory Clarity
a. Grossly vague statutes are unconstitutional. Statutes must be construed in the most favorable terms for the D.
C. Strict Construction (Lenity Doctrine)
a. Where a statute (or the definitions of a word therein) is susceptible to two interpretations – one constitutional and one unconstitutional- the Court should adopt the interpretation resulting in a finding of constitutionality (In Re Banks)

Types of Crimes (Result/Conduct)

A. Result Crime
a. The law punishes because of an unwanted outcome (homicide, arson)
b. Social Harm: The loss suffered from a murder or other violent crime is experienced not only by the immediate victim, but also by society
B. Conduct Crime
a. The law prohibits specific dangerous behavior, such as driving under the influence of alcohol or solicitation to commit murder
b. Social Harm: In one sense, these crimes are punished to prevent social harm but in other sense, they do harm society

Actus Reus

A. Defined:
a. The physical or external part of the crime
b. The comprehensive notion of act, harm, and its connecting link, causation, with actus expressing the voluntary physical movement in the sense of conduct and reus expressing the fact that this conduct results in a certain proscribed harm, i.e. that it causes an injury to the legal interest protected in that crime
B. Two Essential Elements
a. Act/Omission: Must be a voluntary act by D or an omission to perform an act when he had a lawful duty to act
b. Social Harm
C. Voluntary Act
a. Model Penal Code 2.01 Requirement of Voluntary Act; Omission as Basis of Liability; Possession as an Act
i. (1) A person is not guilty of an offense unless his liability is based on conduct which includes a voluntary act or the omission to perform an act of which he is physically capable.
ii. (2) The following are not voluntary acts within the meaning of this Section:
1. (a) A reflex or convulsion
2. (b) a bodily movement during unconsciousness or sleep
3. (c) conduct during hypnosis or resulting from hypnotic suggestion
4. (d) a bodily movement that otherwise is not a product of the effort or determination of the actor, either conscious or habitual
iii. (3) Liability for the commission of an offense may not be based on an omission unaccompanied by action unless:
1. (a) the omission is expressly made sufficient by the law defining the offense; or
2. (b) a duty to perform the omitted act is otherwise imposed by law.
iv. (4) Possession is an act, within the meaning of this Section, is the possessor knowingly procured or received the thing possessed or was aware of his control thereof for a sufficient period to have been able to terminate his possession.
b. The requirement of a Voluntary Act is part of the ACTUS REUS, not the mens rea
c. Where a D was arrested at his home while drunk and taken on the highway, he was involuntarily taken onto the highway and cannot be convicted of being drunk on a public highway (Martin v. State)
d. A father had the necessary actus reus when he voluntarily became drunk and stabbed his son to death (Utter)
e. It is no necessary that all aspects be voluntary. Where an epileptic who knew he was subject to attacks voluntarily decided to drive, she possessed the necessary actus reus when she killed someone. (Decina)
D. Omissions (Negative Acts)
a. Generally, a person had no legal obligation to act even if (1) by not acting harm results, and (2) the person could have acted with no risk to personal safety
i. When a woman was partying with her friend and overdosed, he had no legal duty to help her, even “knowing her to be in peril of her life” (Beardsley)
ii. Bystander Effect (Kitty Genovese)
b. Legal Duty is present where:
i. A statute imposes a duty
ii. One stands in a certain status relationship to another
iii. One has assumed a contractual duty to care for another
iv. One has voluntarily assumed the care of another and so secluded the helpless person as to prevent others from rendering aid
v. A person creates a risk of harm to another
vi. (Some States) Bad Samaritan Laws (like Vermont)
c. A physician does not have a duty to continue treatment once it has proved to be ineffective to a patient who has been reliably diagnosed as in a comatose state from which any meaningful recovery of cognitive brain function is exceeding unlikely (Barber v. Superior Court)
E. Social Harm
a. Defined:
i. The negation, endangering, or destruction of an individual, group, or state interest, which is deemed socially valuable
b. Attendant Circumstances
i. Refer to the objective situation that the law requires to exist, in addition to D’s act or any results that D may cause:
1. “nighttime” in burglary, “property of another” in larceny, “dwelling” in arson, etc…

Mens rea

A. Defined:
a. Narrowly, the mental or internal ingredient required for an offense and specified in the statute;
b. Broadly, a guilty mind, a guilty or wrongful purpose, a criminal intent
B. Specific and General Intent
a. Generally, there is not a lot of agreement on the definitions
b. Specific Intent
i. Some courts say that an offense is “Specific Intent” if the crime requires proof that the actor’s conscious purpose is to cause the social harm of the offense
ii. Or a “specific intent” offense is one in which the definition of the crime expressly:
1. Includes an intent or purpose to do some future act, or to achieve some further consequence (i.e. a special motive for the conduct), beyond the conduct or result that constitutes the actus reus of the offense; or
2. Provides that the actor must be aware of a statutory attendant circumstance.
c. General Intent
i. An offense that does not include the above elements in B(b)(ii)(1) or (2)
ii. The only mental state required in its definition is the intent to do the actus reus of the crime (i.e. battery – intention to do the act of battery is all that is required)
C. Frequently Used Mens rea Terms
a. Intentionally
i. Defined
1. At Common Law, Intentionally causes the social harm if:
a. It is his desire to cause the social harm; or
b. He acts with knowledge that

cient to convict the actor
b. Public Welfare Offenses
i. Factors:
1. Public welfare offenses not derived from common law
2. A single violation of such an offense can simultaneously injure a great number of people, which may explain the legislature’s desire to disregard questions of personal moral guilt, in favor of a sense of the importance of collective interests
3. The standard imposed by the statute is reasonable
4. The penalty is relatively minor, sometimes only involving a fine
5. Conviction rarely damages the reputation of the violator
ii. When a firearm statute was silent on the issue of mens rea and provided a heavy punishment, the court interpreted that mens rea must have been intended or the punishment would not have been so severe (Staples)
c. Non-Public Welfare Offenses
i. Factors
1. Often result in severe punishment
2. Violators are stigmatized, although proof of moral fault is not required
3. Aberrant and especially controversial
ii. When a 20-year old man with an IQ of 52 had sex with a 13-year old girl, his conviction of statutory rape was upheld because it required no mens rea element (Garnett)
d. Model Penal Code §2.02(1)
i. (1) Minimum Requirements of Culpability. Except as provided in §2.05 [violations that cannot result in imprisonment], a person is not guilty of an offense unless he acted purposely, knowingly, recklessly, or negligently, as the law may require, with respect to each material element of the offense.
ii. The Model Penal Code almost does completely away with strict liability
E. Mistake and Mens Rea
a. Mistake of Fact
i. Mistake of fact is not a new or additional concept. It comes out of the mens rea requirement.
ii. Specific Intent Crimes: A D is not guilty if his mistake of fact negates the specific-intent portion of the crime, i.e., if he lacks the intent required in the definition of the offense.
1. If a D receives heroin from X, believing it to be cocaine, and is charged with possession of a controlled substance, he still has the requisite specific intent (receipt of a controlled substance).
iii. Strict Liability Crimes: Since no mens rea requirement exists, mistake of fact does not affect conviction.
b. Mistake (or Ignorance) of Law
i. “Ignorance of the Law Excuses No One” (Except):
1. Reliance in Official Statement of the Law
a. A statute later declared to be invalid
b. Judicial decision of the highest court in the jurisdiction, later determined to be erroneous; or
c. An official, but erroneous, interpretation of the law, secured from a public officer in charge of its interpretation, administration, or enforcement (such as the Attorney General)
2. Fair Notice (The Lambert Principal)
a. Under very limited circumstances, a person who is unaware of a duly enacted and published criminal statute may successfully assert a constitutional defense in a prosecution of that defense (U.S. Supreme Court)