Understanding Criminal Law: Actus Reus, Mens Rea & Key Concepts
Common Law, Actus Reus, and Criminal Liability
Common law is the part of English law that is not created through legislation. It originates from customs and is shaped by judicial decisions. Murder, for example, is a common law offense. While the act of murder is defined by common law, the punishment for it is determined by statute. However, some offenses do not have punishments specified by statute.
Actus reus refers to the physical act or omission that constitutes a crime, along with any relevant circumstances and consequences, excluding the accused’s mental state. To establish criminal liability, the entire actus reus must be proven.
Criminal liability cannot be established without proof of the complete actus reus.
Mens Rea: The Mental Element of Crime
Mens rea refers to the mental state required for a crime, which varies depending on the offense. Common examples include intention, recklessness, and guilty knowledge.
Types of Intention
Direct intention exists when the accused acts with the aim of achieving a specific consequence, regardless of their belief in the likelihood of success.
Oblique intention occurs when the accused foresees a consequence as certain or probable, even if it’s not their primary aim.
Further (or ‘ulterior’) intention describes an intention that goes beyond the immediate consequences of the actus reus, relating to a separate objective.
Recklessness and Negligence
Recklessness (subjective) involves consciously taking an unjustified risk. Oblique intention can be considered a form of recklessness.
Recklessness (objective), better termed negligence, involves taking an unjustified risk without awareness, even though the accused should have been aware.
Negligence is the failure to meet a reasonable standard of conduct regarding a foreseeable risk, implying blameworthy carelessness.
Guilty Knowledge
There are three degrees of guilty knowledge:
- Actual knowledge, which can be inferred from the accused’s behavior.
- Willful blindness or connivance, where the accused deliberately avoids knowledge.
- Constructive knowledge, where the accused should have known something but failed to make reasonable inquiries.
Motive, Ignorance, and Mistake
Motive is a secondary intention and generally irrelevant to criminal liability. Distinguishing between ‘further intention’ and ‘motive’ can be challenging.
Ignorance and mistake of law are typically not valid defenses against criminal liability.
Burden and Presumption of Proof
Burden of proof generally rests with the prosecution to prove both actus reus and mens rea beyond a reasonable doubt. The jury decides questions of fact, but the judge can intervene if evidence is insufficient.
Burden of adducing evidence also lies with the prosecution, while the accused typically needs to provide enough evidence to support a defense.
Presumptions can assist in proving facts:
- Irrebuttable presumption of law: The jury must accept the presumed fact.
- Rebuttable presumption of law: The jury must accept the presumed fact unless sufficient contrary evidence is presented.
- Presumption of fact: The jury may infer a fact based on the proof of another fact.
Proof of Mens Rea
The act itself can suggest that the accused acted voluntarily, knowingly, and with the intention of causing its usual consequences.