2.1 Elements of a Crime

• Every crime generally requires two essential elements:
  • Actus Reus (AR) – the guilty act (conduct element).
  • Mens Rea (MR) – the guilty mind (mental element).
• Together these demonstrate fault and ensure a person is only criminally liable where both the act and intention coincide.
• Some offences are strict liability, where no mens rea is required for part (or all) of the offence — but these are exceptions.
• This section focuses on Actus Reus.

2.1.1 Actus Reus

Definition

• Actus Reus refers to the external or physical element of a crime.
• It covers what the defendant does (conduct), the circumstances in which it is done, and sometimes the consequences that result.
• In Latin, “actus reus” means “guilty act.”
• Distinguished from mens rea, which concerns the mental state.
• Case Definition:
  • In Hill v Baxter (1958), the court explained that an act must be voluntary to form actus reus. The judge gave the example of being attacked by a swarm of bees while driving — not voluntary.

Elements of Actus Reus

• Actus reus can take several forms:
  1. Conduct – the act itself.
  2. Consequence – result crimes where the conduct must cause a particular outcome.
  3. State of Affairs – rare offences where simply being in a situation is enough.
  4. Omissions – failure to act when under a legal duty.

1. Conduct Crimes

• Crimes where the prohibited act itself is sufficient, regardless of the outcome.
• Example:
  • Perjury – lying under oath. No need to prove consequence.
  • Drink driving under the Road Traffic Act 1988 – offence complete upon driving with alcohol above legal limit.
• Key Point: The mere conduct is the crime.

2. Consequence Crimes

• Crimes where actus reus requires that the defendant’s act causes a particular result.
• Example:
  • Murder – requires unlawful killing (consequence: death).
  • Assault occasioning actual bodily harm (ABH) – under s.47 Offences Against the Person Act 1861, consequence must be harm.
• Key Case:
  • R v White (1910): Defendant put poison in mother’s drink, but she died of a heart attack before drinking it. No actus reus for murder (no causation), though liable for attempted murder.
  • Demonstrates importance of causation in consequence crimes.

3. State of Affairs Crimes

• Liability for being found in a particular condition or situation, even without action.
• Often strict liability.
• Examples:
  • R v Larsonneur (1933): Defendant, a French national, deported from Ireland to England against her will. Charged with “being an alien found in the UK without permission.” Liability despite involuntariness.
  • Winzar v Chief Constable of Kent (1983): Defendant, drunk, removed from hospital by police and placed on highway. Convicted of “being found drunk on a highway.”
• Criticism: Harsh, as no voluntary act needed.

Written and Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change AS Level Law Full Scale Course

4. Omissions (Failure to Act)

• General Rule: No liability for failing to act — “no liability for a bad Samaritan.”
• Exceptions: Liability arises if there is a legal duty to act and the duty is breached.

Categories of Duty

1. Statutory Duties
   • Duties imposed by statute.
   • Example:
     • s.6 Road Traffic Act 1988 – failing to provide a breath specimen is an offence.
     • Children and Young Persons Act 1933 – parents responsible for neglect of children.
2. Contractual Duties
   • Duty arising from contract of employment.
   • R v Pittwood (1902): Railway gatekeeper failed to close crossing gate, person killed by train. Guilty of manslaughter due to contractual duty.
3. Duty Arising from Relationship
   • Certain relationships impose duty to care.
   • R v Gibbins & Proctor (1918): Father and mistress failed to feed child, who died. Both convicted of murder.
4. Voluntary Assumption of Duty
   • Voluntarily taking responsibility for another person.
   • R v Stone & Dobinson (1977): Defendants failed to care for elderly relative, leading to her death. Guilty of manslaughter.
5. Duty Through Creation of a Dangerous Situation
   • If defendant creates a dangerous situation, duty arises to take steps to prevent harm.
   • R v Miller (1983): Defendant accidentally set fire to mattress, failed to act. Convicted of arson.
6. Duty of Officials/Public Position
   • Public office may create a duty to act.
   • R v Dytham (1979): On-duty police officer failed to intervene in violent attack. Guilty of misconduct in public office.

• Critical Analysis:
  • Omissions liability ensures responsibility, but critics argue it undermines freedom by punishing inaction.
  • Contrast with continental systems (e.g., France), where there is a positive duty to rescue.

Voluntariness of Actus Reus

• To constitute actus reus, conduct must be voluntary.
• Case: Hill v Baxter (1958): No liability where driver lost control due to swarm of bees.
• Case: R v Quick (1973): Nurse with diabetes assaulted patient while hypoglycaemic (due to insulin and not eating). Involuntary, so not actus reus.
• Case: R v Mitchell (1983): Defendant pushed man in post office queue, who fell onto elderly woman, killing her. Defendant still liable as original act voluntary, despite consequences being indirect.

Written and Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change AS Level Law Full Scale Course

Causation in Actus Reus

• For consequence crimes, prosecution must prove defendant caused the result.
• Two aspects:
  1. Factual Causation
  2. Legal Causation

1. Factual Causation

• “But for” test — would the result have occurred but for defendant’s conduct?
• Case: R v White (1910) – But for D poisoning drink, mother still died → no factual causation.
• Case: R v Pagett (1983): D used girlfriend as shield during police shootout; police shot her. “But for” D’s actions, she would not have died. Factual causation established.

2. Legal Causation

• Defendant’s act must be an operating and substantial cause of the result.
• R v Smith (1959): Soldier stabbed, dropped twice on way to treatment, poor medical care contributed to death. Still liable as wound was substantial cause.
• R v Cheshire (1991): Negligent medical treatment only broke chain if “so independent and potent” that D’s act was insignificant. D still liable.
• R v Jordan (1956): Medical negligence broke chain: victim given drug he was allergic to after stab wound had almost healed.

Novus Actus Interveniens (Intervening Acts)

• Third-party acts, victim’s acts, or natural events may break chain of causation.
• R v Roberts (1971): Girl jumped from moving car to escape sexual advances, injured. D liable — foreseeable reaction.
• R v Williams & Davis (1992): Hitchhiker jumped from car due to robbery attempt, died. Not foreseeable → chain broken.

Written and Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change AS Level Law Full Scale Course

Thin Skull Rule

• Defendant must “take victim as found.”
• R v Blaue (1975): Victim stabbed, refused blood transfusion due to religious beliefs, died. D liable for death — refusal did not break chain.
• Principle ensures personal characteristics of victim do not reduce liability.

Criticisms of Actus Reus Rules

• Omissions liability criticised as inconsistent — duties recognised in limited categories only.
• Causation cases inconsistent, especially with medical negligence.
• State of affairs offences seen as unfair (liability without voluntary act).
• Despite this, actus reus remains central to ensuring justice, fairness, and legal certainty in criminal law.