A more recent version of these Actus Reus — Omissions And Causation notes – written by Oxford students – is available here.
The following is a more accessble plain text extract of the PDF sample above, taken from our Criminal Law Notes. Due to the challenges of extracting text from PDFs, it will have odd formatting:
TOPIC 1 --- CRIMINAL LAW --- ACTUS REUS: OMISSIONS AND CAUSATION AR: the conduct element of a crime; what the D must have done / failed to do. MR: mental element --- intention, recklessness, or negligence. ACTUS REUS Voluntary act requirement: in every criminal case there should be a voluntary act --- if the D is not acting voluntarily the D will be said to be an automaton and not guilty of an offence because the AR and MR will not have been proved. The general principle that a crime must involve an act of the defendant is subject to two important caveats:
1. it is not really clear what is meant by 'act' here
2. There are a number of crimes which seem to be exceptions to the rule, including: a. Omissions can give rise to criminal liability --- in such cases the failure to act can constitute the AR of the crime. b. The AR of an offence is defined as a state of affairs that may not involve an act (just circumstances) e.g. possession of a firearm. c. D can, in some circumstances, be responsible for the acts of another person. NB: whether the above are true exceptions turns on how we define 'act'. BASIC PRINCIPLES The Dadson principle: a defendant can't rely on justifying circumstances of his actions of which he isn't aware. This demonstrates that justifications aren't just measured objectively (i.e. were the actions reasonable?) but rather has subjective elements (requires that D was aware of and acted due to the justificatory reasons). Dadson 
Facts: D, a constable, shot V, wounding him when he was running away from a copse. Unknown to D, V had just committed a felony in the copse (and therefore it would have been lawful to shoot him). D was convicted of having feloniously wounded V. Held: D was convicted of having feloniously wounded V. Yes. The prisoner was not justified in firing at Waters, because the fact that Waters was committing a felony was not known to the prisoner at the time. Deller 
Facts: D sold a car, stating that it was free of encumbrances. In fact, he thought the car was encumbered, because he had earlier mortgaged it to a finance company. Deller was charged
with obtaining the proceeds of a car sale under false pretences. As it happened however, the earlier mortgage was invalid and hence the car was unencumbered --- by chance his pretence was not false. Hilbery J: D could therefore not be convicted as he had broken no law. Nullum crimen sine lege: no one should be convicted of a crime unless what is done is in law a crime. The above two cases illustrate the distinction between an absent element defence (Deller) (i.e. no AR) and an affirmative defence (Dadson). In the latter case, the elements of the crime (AR and MR are made out) but the defence operates to make the conduct not criminal; in the former, there is no crime at all because the AR is not established. No voluntary act Situational offences, where the D is guilty for 'being in a particular situation or state of affairs' (e.g. being drunk in charge of a vehicle, or possessing a drug or offensive weapon) are compatible with the voluntary act requirement as they involve a prior act --- e.g. getting drunk. Larsonneur 
Facts: French woman deported from UK and told not to return. She went to Ireland. Ireland deported her back to England under police escort, and then handed over to UK authorities. Charged with being an alien whose leave to land had been refused. Held: her conviction should be upheld. Comment: There is nothing intrinsically wrong in criminalising states of affairs, so long as the class of potential defendants can be clearly identified. However, there should be a further requirement - that the defendant should be able to do something about it. It is the failure of English law to observe this in Larsonneur that makes the decision so objectionable. OMISSIONS There is no general omissions liability in English law --- a defendant is only guilty of a crime when failing to act where he or she is under a duty to act.
1. crimes that cannot be committed by omissions There are certain crimes that cannot be committed by omissions --- e.g. where the relevant statute stipulates that a positive action is required. Under the Protection from Eviction Act 1977, for example, proof is required of the D "doing acts calculated to interfere with the victim's peace and comfort" --- under this act therefore if a landlord fails to carry out
alterations on the V's house (and this leaves the premises uninhabitable) the failure to do so is not a crime (see Ahmad ).
2. When the D is under a duty to act The D can be placed under a duty to act in a number of ways:
1. Statutory duty: e.g. s.6 of the Road Traffic Act 1988 states that it's an offence to fail to provide a breath sample when requested.
2. Duties of law enforcement: police officers are under a duty to assist members of the public in danger. Further, if a police officer calls on a citizen to assist him to restore the peace, the citizen is under a duty to offer assistance.
3. Contractual duty: Pittwood : D was employed as a gatekeeper on a railway line and failed to perform his duty of shutting the gate to a road over the line --- as a result a cart hit the man was killed. D was liable for manslaughter because he was required under his contract to ensure the gate was shut.
4. Assumed duties: people who voluntarily assume responsibility for another's welfare will be under a duty to care for them. This may be express or implied. Some arise automatically (e.g. a parent is under a duty to care for a child --- so the failure to feed a child leading to starvation, although an omission, will still lead to an offence). The leading case here is as follows: Stone and Dobinson 
Facts: the Ds were Stone (below average intelligence, partially deaf, almost blind), and Dobinson (described by court as 'ineffectual and inadequate'). Stone's sister, Fanny, came to live with them (and their disabled son, Cyril). F suffered from anorexia nervosa; often denied herself food, and stayed in her room for days at a time. Once, the police found her wandering the street. The Ds then tried to find her doctor but unable to do so. F grew weaker, became confined to bed. Despite requests from neighbours, appellants did nothing. F was then found dead, naked, dirty, in appalling conditions. Appellants convicted of manslaughter. Appealed. Lane LJ:
1. The facts justified a finding that S and D had assumed a duty of care and were obliged either to summon help or to care for the sister themselves when she became infirm;
2. The breach of duty which had to be established was a reckless disregard of danger to her health and welfare by indifference to an obvious risk of injury to health or by actually foreseeing the risk and determining nevertheless to run it. This was not a situation analogous to the drowning stranger. They did make efforts to care. They tried to get a doctor; they tried to discover the previous doctor. The appellant Dobinson helped with the washing and the provision of food. NB: Prosecution must prove duty of care exists; this can only be assumed as a matter of choice - inaction is insufficient.
Herring: At the heart of the decision is the finding that S+D had voluntarily assumed responsibility to care for F. The decision is highly controversial due to the low capabilities of the accused. It is not clear from the case what was crucial to the finding of the DoC
--- was it the biological relationship, the undertaking of responsibility for care, or a combination of the two?
3. Continuing act See Fagan below --- case of a car on a policeman's foot. Wasn't a crime when he drove onto the foot (no MR) but by leaving it there (an omission) he committed a crime because it was held to be a continuing act (so there was coincidence of AR and MR).
4. Creating a dangerous situation Where someone has created a dangerous situation they may be under a duty to act to prevent harm resulting. R v Miller 
Facts: Miller, drunk, fell asleep with lighted cigarette in hand in house in which was staying. Woke to discover the mattress was on fire. Moved out of the room into a neighbouring room and went back to sleep. Convicted of arson. Question for HL: whether the actus reus of the offence of arson is present when a defendant accidentally starts a fire and thereafter, intending to destroy or damage property belonging to another or being reckless as to whether any such property would be destroyed or damaged, fails to take any steps to extinguish the fire or prevent damage to such property by that fire?' Lord Diplock:
? "The conduct of the accused, throughout the period from immediately before the moment of ignition to the completion of the damage to the property by the fire, is relevant; so is his state of mind throughout the period."
? "It is sufficient to constitute the statutory offence of arson if at any stage in that course of conduct the state of mind of the accused, when he fails to try to prevent or minimize the damage which will result from his initial act, although it lies within his power to do so, is that of being reckless whether property belonging to another would be damaged..." The problem here is that there is a requirement that AR and MR coincide in time --- here the AR seems to be the dropping of the cigarette; but at that point there was no MR. However, at the time D had the MR (when he realised there was a fire) he wasn't doing anything (he omitted to take action). There are two ways of explaining this case:
(1) Duty theory: [Ashworth 1989] the broader proposition that whenever a person creates the risk of harm by an act (even if unintentional) and subsequently realises this risk, there is a duty to take steps to avert or minimise that risk. (2) Continuing Act theory: Miller's initial act was regarded as a continuing act until the result was produced. The conduct of the accused, throughout the period from immediately before the moment of ignition to the completion of the damage to the property by the fire, is relevant; so is his state of mind throughout that period. Since arson is a result-crime the period may be considerable, and during it the conduct of the accused that is causative of the result may consist not only of his doing physical acts which cause the fire to start or spread but also of his failing to take measures that lie within his power to counteract the danger that he has himself created. Bibek: There is no liability in criminal law for an omission to act unless there is a legal duty to act imposed either by common law or by statute. In so far as Fagan established a principle that mens rea can supervene and render culpable a previous innocent act it was wrongly decided. It is distinguishable from the present case because there is no evidence that the appellant "acted" in any voluntary or deliberate sense. If there is a duty to act, what is the content of the duty? The answer here is to do what is reasonable in the circumstances --- one issue that is not yet resolved is whether the D is required to do what is reasonable for him / her or what would be reasonable for an ordinary person in his / her shoes. The CA in Stone / Dobinson did not address the issue. It must be shown that the omission caused the harm --- i.e. had the D acted reasonably in accordance with the duty the harm would not have occurred. For example:
? Dalloway : D driving a cart without a proper grip on the reigns; a young child ran out in front of the cart and was killed. Held that it had to be shown that if the D had been driving properly the child would not have been killed.
5. distinguishing between omissions and acts Although the law draws a sharp line between the two, there can be great difficulties distinguishing them. This may lead us to question whether we should place a lot of weight on the distinction. An example of the difficulties in this area is Speck  --- a child innocently placed her hand on a man's penis and he did nothing to move it. Was this an act or an omission? It was held to be an act, but it might more properly be thought of as an omission. The leading case in this area is now the following: Airedale N.H.S. Trust v Bland 
Facts: Tony Bland (17) suffered irreversible brain damage as a result of the Hillsborough Stadium Disaster and was left in a persistent vegetative state. He was fed by tubes, had no cognitive function, and various infections were treated, keeping him alive. The consensus of
medical opinion was that there was no hope for his improvement or recovery. The Airedale N.H.S Trust, with the support of his parents, sought a declaration from the court permitting the discontinuation of his life-sustaining treatment. House of Lords: characterise the dis-continuation of life-sustaining treatment as an omission and not an act.Lord Mustill: Argues from five points: o (i) "The cessation of nourishment and hydration is an omission not an act" o (ii) "cessation will not be a criminal act unless the doctors are under a present duty to continue the reigeme." o (iii) Bland, when admitted, could not make a decision about his care --- the doctors made it for him in his best interests. At this time there was a chance he could improve. o (iv) "All hope of recovery has now been abandoned. Thus, although termination of his life is not in the best interests of Anthony Bland, his best interests in being kept alive have also disappeared, taking with them the justification for the non-consensual regime and the correlative duty to keep it in being." o (v) "Since there is no longer a duty to provide nourishment ... a failure to do so cannot be a criminal offence." o "Now that the time has come when Anthony Bland has no further interest in being kept alive, the necessity to do so, created by his inability to make a choice, has gone; and the justification for the invasive care and treatment together with the duty to provide it have also gone. Absent a duty, the omission to perform what had previously been a duty will no longer be in breach of the criminal law."
Note: the decisions seems right, although it is analytically unsatisfying --- is the doctors act in turning of life support machines really distinguishable from the interloper who comes into the hospital and turns them off?
CAUSATION For some crimes it is necessary to show not only that the D performed an act, but that the act caused a particular consequence. E.g. in murder it must be shown that the accused caused the death of the victim. The hardest cases are the ones where it is not clear which of two people caused the result. The courts have consistently stated that causation is a matter of common sense (see, for example, Kennedy ) and is a question of fact for the jury (i.e. no scientific definition of causation) --- although it is open to the judge to give direction to the jury.
Responsibility: at the heart of the notion of causation in criminal law is the assumption that each person is responsible for his / her actions. Therefore, a person's background is not relevant to whether they are causally responsible for a certain action. Factual / but for causation The test for factual causation requires the jury to consider whether, but for the D's actions, the harm would have occurred at the time it did and in the way that it did. The leading case on 'but for' causation is now the following:
Facts: Hughes was driving along a carriageway when a vehicle driven by V swerved across the road and collided with him. V, who died from his injuries, was under the influence of heroin at the time. It was accepted that D's driving was faultless, but he was driving without insurance or a full license. D was convicted by Court of Appeal of an offence contrary to s 3ZB of the Road Traffic Act 1988. Supreme Court:?
Deciding the case: "He [V] might easily have gone off the road and hit a tree, in which case nobody would suggest that his death was caused by dangerous driving ... Juries should be directed that it is not necessary for the crown to prove dangerous driving, but that "there must be something open to proper criticism in the driving of the defendant, beyond the mere presence of the vehicle on the road." ... From the use of the expressions 'causes ... death ... by driving' ... section 3ZB requires at least some act or omission in the control of the car, which involves some element of fault ... which contributes in some more than minimal way to death." His presence on the road is not enough." On but for causation: "The law has frequently to confront the distinction between "cause" in the sense of a sine qua non without which the consequence would not have occurred, and "cause" in the sense of something which was a legally effective cause of that consequence. The former, which is often conveniently referred to as a "but for" event, is not necessarily enough to be a legally effective cause. If it were, the woman who asked her neighbour to go to the station in his car to collect her husband would be held to have caused her husband's death if he perished in a fatal road accident on the way home. In the case law there is a well recognised distinction between conduct which sets the stage for an occurrence and conduct which on a common sense view is regarded as instrumental in bringing about the occurrence.
Key point: factual causation cannot be used as the general rule for causation, however, because it is far too wide. Something cannot be a legal cause unless it is a factual cause, but not all factual causes are legal causes. Legal causation
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