1) Actus Reus can be an act, omission, or state of affairs. Omissions usually do not constitute a crime unless there is a legal duty to act that arises from statutes, contracts, relationships, voluntary undertakings, an official position, or setting dangerous events in motion. 2) Causation has two tests - the "but for" test of factual causation and the test of legal causation which examines if the contribution was more than minimal. Several exceptions apply like the thin skull rule, chain of causation, and fright or flight rule. 3) There is debate around what constitutes breaking the chain of causation, particularly regarding victim actions like

1. Actus Reus
Omissions and Causation

2. Actus Reus- an Introduction
• Actus Reus is the physical
part of a crime.
• It can be an act.
• It can be a failure to act
(an Omission).
• It can be a state of affairs
case- Larsonneur.
• It usually has to be
voluntary with D
conscious of his actions-
Hill V Baxter.

3. Omissions- Introduction
• This is a failure to act. It usually won’t
make D guilty of an offence. It means
that if I stood there and watched
someone died I wouldn’t be guilty of an
offence.
• There are however some exceptions to
this rule…

4. The Duties
• Statutory Duty- A duty imposed by a statute. Road
Traffic Act- Failure to provide a specimen of breath.
• Contractual Duty- A duty arising because of a
contractual agreement. Pitwood.
• Relationship Duty- A duty arising because of a
relationship. Gibbons and Proctor.
• Voluntary Duty- A duty someone has taken
voluntarily. Stone and Dobinson.
• A duty because of official Position- Where a certain
job or position creates the duty. Dytham.
• A duty because a dangerous set of events has been
set in motion- Where D has set some dangerous
events in motion and omits to act upon it. Miller

5. Further Duties
• Khan and Khan says there
could be more than those
six duties.
• Duty of Doctors- If it is
within the patients best
interest, the Doctor can
withdraw feed from a
patient. Airedale NHS
Trust V Bland.
• Euthanasia is unlawful.

6. Good about Omissions
• It is fair that the Police have a duty to
protect the public.
• It is good that parents have a duty of care
over their children.
• It is fair that those who set a dangerous
chain of events in motion are expected to
take reasonable steps to solve it.
• It is fair that those who undertake duties
voluntary are expected to live up to what
they agree to do.

7. Bad about Omissions
• Khan and Khan says there could be more than
six duties. It does not specify what they are and
for what they apply. Someone could be omitting
and not even know it.
• Duties from a statute can be applied to lots of
different scenarios, too many for anyone to
know.
• Too many statutes impose duties. It is
impossible for someone to know them all.
• Duty of Doctor’s is a difficult subject. Nothing
defines the line between best interest and
euthanasia.

8. Causation- Introduction
• Causation tests whether someone should
be blamed for an offence or not. There are
two tests to answer this question.
• The first test is Factual Causation. This
asks if D committed the Actus Reus or not.
“But for D’s actions, would V be in that
situation”.
• The second test is Legal Causation. This
tests whether it is fair to blame D or not.
Has D made more than a minimal
contribution to the consequence.

9. Causation- The Tests
• Factual- “But for D’s actions would V be in
situation?”. This means that if D hadn’t
done what he apparently did, would V still
be in the consequence? Pagett.
• Legal- The legal test tests whether it is fair
to blame D or not. This tests whether D
made more than a minimal contribution
and is it fair to blame D from this
contribution. Marchant and Muntz.

10. Causation- A few Points
• More than one act can contribute to the
consequence. The rule is that D’s act
should be more than minimal.
• D’s actions don’t have to be the main
cause or a substantial cause, it just has
to be more than minimal. There should
be more than a slight trifling link
between D’s act and the outcome.
Kimsey.

11. Causation- The Thin Skull Rule
• D takes V as he finds him.
• If V has some other
condition that D is
unaware of, and D
commits the Actus Reus
and the unknown
condition is made worse as
a result, D will still be
liable. Blaue.

12. Causation- Chain of Causation
• There is a chain between what D did and
the result on V.
• This chain can be broken by the act of a
third party. This could be medical.
• It can be broken by V’s own acts.
• It can be broken by an unpredictable
natural event.
• To break the chain it must be very separate
from D’s original act.
• If D’s act causes a likely response from a
third party he is still likely to be guilty.
Pagett.

13. Causation- Medical Treatment
• Medical treatment is unlikely to break
the chain of causation unless it is so
potent and so separate from D’s act it
renders the act as insignificant.
• Smith and Cheshire show poor medical
treatment with D still being guilty. This
is usually the way it goes.
• Jordan showed D being guilty. This is
rare and unusual.

14. Causation- Fright or Flight Rule
• If V tries to escape and dies as a result of
the escape or during the escape, or even
becomes more injured, it is likely D will
still be guilty. Roberts. Corbett.
• If V’s actions are reasonably foreseeable it
is likely D will still be guilty. Marjoram.
• The chain will be broken if D does
something so daft or unexpected that no
reasonable person could foresee it.
Williams.

15. Causation- V’s Self Neglect
• If V mistreats or neglects his injuries it
will not break the chain of causation.
Holland. Blaue. Dear.
• D must accept that V could be irrational,
stupid, religious, afraid of hospital or
refuses treatment. D will still be guilty.

16. Causation- The Good
• It is fair that it tests that D actually did
it and if it is fair to blame D for it.
• It is fair that D gets convicted if thin
skull rule appropriate, as it was his
actions that caused it.
• It’s fair that unpredictable natural
events break the chain of causation.

17. Causation- The Bad
• It is unfair that if V refuses treatment D is
still responsible.
• It is unfair that if bad medical treatment
kills V, D could still be liable.
• It is unfair that V not taking care of
himself doesn’t break the chain.
• It isn’t fair that if D’s act isn’t the main
cause he may still be guilty.
• What defines a “slight or trifling link?” or
“minimal contribution?”