Criminal Law
Lecture 1
What is Criminal Law?
Criminal law is the body of law that relates to crime. It regulates
social conduct and proscribes threatening, harming, or otherwise
endangering the health, safety, and moral welfare of people. It
includes the punishment of people who violate these laws.


Moreover, criminal law:
Defines crime and its elements;
Provides proportional punishment for the crime;
Classifying Criminal Law

Crimes ‘mala in se’ - Acts which are wrong in themselves. The
conduct is unlawful because the transaction or contact between
people is unnatural or immoral. Examples include murder, rape,
burglary, and so forth.

Crimes ‘mala prohibita’ - Acts which are wrong because
prohibited. The conduct is unlawful because it infringes on
other's rights or just because it is prohibited. Examples include
drunk driving, gambling, and so forth.

Crimes ‘distinguished from torts’ - Victims can sue criminals in
tort action, and double jeopardy does not prohibit tort and
criminal action for the same conduct. Tort Law grew out of
Criminal Law, and involves the concepts of fault and liability but
does not carry the social condemnation of Criminal Law. That's
why a different standard of proof exists for torts. Examples
include libel, slander, trespass, wrongful death, and so forth.
Elements of a Crime
(Hall, 1949):
By definition, a crime is:

legally proscribed (the concept of Legality)

human conduct (the concept of Actus Reus)

Ablameworthy frame of mind (the concept of Mens Rea)

causative (the concept of Causation)

of a given harm (the concept of Social Harm)

which coincides with (the concept of Concurrence)

for which punishment is provided (the concept of
Punishment)
Legality

nullum crimen sine poena - no crime without
punishment

nulla poena sine lege - no punishment without
law
Actus Reus
Guilty Act
An act can consist of commission, omission or
possession.
Omission
Omission involves a failure to engage in
necessary conduct resulting in injury. As with
commission acts, omission acts can be reasoned
causally using the but for approach. But for not
having acted, the injury would not have
occurred.
Voluntariness
The conduct must be voluntary
Epileptic seizure?
People v. Decina (1956) (motor vehicle)
Unconsciousness or Sleep
Automatism - ‘the existence in any person of behaviour of
which he is unaware and over which he has no conscious
control.’
Hill v Baxter – ‘If the jury are left in real doubt whether or
not the accused acted in a state of automatism...they
should acquit because the necessary mens rea has not
been proved beyond a reasonable doubt.’
Thus, a person suffering from sleepwalking, epilepsy or
other convulsive or reflexive disorder, who kills another,
steals another's property, or engages in other facially
criminal conduct, may not have committed an actus reus,
for such conduct may have been elicited unconsciously.
Voluntariness – Omission
Voluntariness includes omission - the actor
voluntarily chose to not behave in and,
consequently, caused an injury.
The purposeful, reckless, or negligent absence of
an action is considered a voluntary action and
fulfills the voluntary requirement of actus reus
Mens Rea
Mens Rea means ‘guilty mind.’
Actus non facit reum nisi mens sit rea - ‘the act is not culpable
unless the mind is guilty.’
Necessary element of a crime
Thus there must be an actus reus, or ‘guilty act,’ accompanied by
some level of mens rea to constitute the crime with which the
defendant is charged.
The actus reus and mens rea of homicide in a modern criminal
statute can be considered as follows:

actus reus: any conduct resulting in the death of another
individual;

mens rea: intent or knowledge that the conduct would result in
the death.
Causation
Causation is the ‘causal relationship between
conduct and result.’ That is to say that causation
provides a means of connecting conduct with a
resulting effect, typically an injury.
Strict Liability
Standard for liability – a person is legally
responsible for the effects of his/her act/omission
regardless of culpability (fault – typically the
presence of mens rea).
Strict liability often applies to vehicular traffic
offenses. In a speeding case, for example,
whether the defendant knew that the posted
speed limit was being exceeded is irrelevant. The
prosecutor would need to prove only that the
defendant was operating the vehicle in excess of
the speed limit.
Criminal Law v International Criminal
Law?