(麥 嘉 豪 )
Adjunct Associate Professor
BRIEF - Lecture 1
(B). What is a crime?
(C). Principles of Criminal Liability
Chapters 1, 2 and 4 of the Workbook
and some additional information
(A) General Introduction
2. Law regulates conduct in society.
3. Division of Law into civil and criminal law.
4. Civil Law – disputes between individuals.
5. Criminal Law
- disputes between the state and individuals.
- it is about proscriptive (prohibited) and
prescriptive (preferred) rules
6. Prosecution by the State of bad conduct.
State is generic term.
(B) What is a Crime?
1. Morality and Illegality;
2. A crime is an injury against society.
Harmful conduct against societal interests.
3. Essence is PUNISHMENT
4. Criminal Law acts as an instrument of
and aims to
5. By achieving the FUNCTIONS
prosecution, due process, and sentencing)
6. Crimes are called offences.
- created by statute or common law
- summary offences;
- indictable offences;
- offences triable either way;
- arrestable and non-arrestable offences.
Basic elements of a crime
7. Ancient Principles of Criminal Law:
- Nullum Crimen Sine Poena;
- Nulla Poena Sine Lege;
- Actus Non Facit Reum Nisi Men Sit Rea;
- Lex Prospicit Non Respicit.
8. Examples of Crimes:
- Against state
- treason, sedition, etc.
- aims at protection of national security
- Against persons
- e.g. murder, manslaughter, wounding,
rape, assault, etc.
- aims at protection of persons against
- Against property
- e.g. theft, robbery, fraud, forgery, etc.
- aims at protection of private property .
- Against public order
- riot, drugs, motor vehicle offences,
possession of offensive weapons, etc
- aims at protection of public order,
peace and safety .
- Against habitation
- e.g. burglary, etc.
- aims at protection of safety & security in
- Against public morals
- prostitution, incest, obscenity, sodomy,
- aims at protection of traditional morality.
- Against administration of justice
- e.g. bribery, resisting arrest, perjury etc.
- aims at protection of efficient / honest
9. Presumption of innocence
- Woolmington v DPP 1935
- Art. 11 BORO Cap. 383; Art. 39 Basic Law
- Accused – the person arrested is presumed
innocent of the offence until proven
- Adversarial system
- CX – Inquisitorial system – reverse burden.
10. Burden of Proof on prosecution.
- on all elements of offence.
11. Standard of Proof
Proof by evidence of guilt by the prosecution
beyond a reasonable doubt.
Right of Silence by accused.
N.B. In some limited cases accused bears legal burden of
e.g. – insanity; diminished responsibility.
Accused discharges this on a balance of probabilities
Basic elements of criminal liability
(1) Actus Reus – result of
(2) Mens Rea –
frame of mind
(3) Absence of any defence.
(i) refers to all external elements of a crime.
(ii) relates to the facts or all surrounding
(iii) involves a positive act;
(iv) can include an omission to act where
accused is under a legal duty to act;
R v Pittwood 1902
Gate keeper at level crossing failed to close gate
causing death of victim.
Stone v Dobinson 1977
Victim unable to look after herself. D’s undertook her
care. Not call for medical help. Died.
R v Gibbons & Proctor 1918
D’s child died of starvation and neglect.
R v Larsonneur 1933
French lady brought to U.K by force by Irish
(v) duty to act may arise from creating a
R v Miller 1983
Trespasser set fire to mattress.
CX. Should a drug trafficker owe a duty of
care to their clients?
R v Khan 1998
(vi) Causation must be established
Unlawful act of Defendant
R v Cox 1992
Lethal injection by doctor
In law and on the facts
- factual causation
R v White 1910
the “but for” test
R v Carey 2006
V 17 years old was punched by D in affray. V ran uphill
to hospital. Died of a heart attack. No knowledge of
condition by victim, D or hospital.
Can you say victim would not have died “
R v Smith 1959
D stabbed V in a fight. V rushed to “medical
station” in army barracks. V dropped twice on way.
Given “bad” medical treatment. No blood
transfusion. V died.
Original wound still substantial threat
Defendant must take his victim as he
R v Blaue 1975
Jehovah’s witness stabbed by D. Refused blood
R v Dear 1996
Within range of responses
Unforeseeable intervening acts?
R v Pagett 1983
Using girlfriend as a “shield”.
Actus Reus must be voluntary act
- acts under hypnosis;
- acts done whilst sleepwalking;
- words (cx assault/conspiracy) .
(2) Mens Rea
refers to state of mind of accused.
- is the awareness of his actions.
Most crimes require this
Mens Rea – refers to 3 states
(aim, purpose or desire)
- doing something purposively
- doing something knowingly
(subjectively aware of a substantive certainty
or practical certainty of result)
(conscious disregard of a substantial
and unjustified risk)
(failure to achieve the standard expected
of a reasonable person)
Strict Liability Offences
No need to show mens rea.
These are regulatory offences.
Statutory in nature.
Include construction site safety, public health,
pollution, public nuisance etc
Cundy v Le Cocq 1884
D sold liquor to a drunken person. D did not know
V was drunk. Convicted.
What if offence is silent on mens rea?
For most offences, under the common law, there
is a presumption of some mens rea being
B (a minor) v DPP 2000
B – a 15 year old boy.
Repeatedly asked a 13 year old girl on a bus for oral sex.
B was convicted of inciting a child under 14 to commit an
act of gross indecency.
B honestly thought V was over 14.
On appeal to House of Lords, it was held that:
this is not strict liability offence;
mens rea is the subjective honest belief by D that V
was over 14.