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Module 4 · Manslaughter

Unlawful and dangerous act manslaughter appears in every paper since 2021, and negligent manslaughter, usually by omission, in five of six. The two forms are alternatives, and the H1 skill is choosing and sequencing them. Manslaughter is a single common law offence with alternative forms, so the two routes run in the alternative to one conviction, not both on the one act.

Cases at a glance

Unlawful and dangerous act manslaughter

• Caused the death. Apply M1 causation. The dangerous act must be a substantial or significant cause (Aidid). But-for alone is only the threshold. Where a single punch is in play, s 4A(4) extends the causal link to death from a resulting impact. One chain break is a fixture here: where the accused supplies a drug and the victim freely and knowingly self-injects, that free, deliberate and informed act breaks the chain and UDAM fails (Burns; Dalby). Administering the drug to the victim is different and can found liability (Cato).
• Conscious, voluntary and deliberate. Apply M1 voluntariness (Ryan). The prosecution need not prove an intention to kill or to cause really serious injury (Haywood; Vollmer). This element rarely carries the fight, so note it in a sentence unless the facts raise reflex or accident.
• Unlawful. The act must breach the criminal law (Wilson; Pemble), and it appears only offences requiring proof of mens rea qualify (Nguyen), so civil negligence is not enough (Lamb). Prove every element of the base offence, usually common law assault by apprehension or force (Fagan), including its fault element, for which recklessness suffices (Venna). An act in self-defence is not unlawful (Cornelissen), and the act need not be directed at the deceased (Mitchell), so a bottle thrown at one guest that kills another can still found UDAM.

How unlawfulness is fought on facts

The defence attacks the base offence, not the label. Lamb is the model: friends fooling with a rifle both believed empty, the deceased laughing and apprehending nothing. No apprehension and no assault fault means no assault and no UDAM (Lamb; Fagan). Say in one sentence that the proper route is then negligent manslaughter. Do not reason backward from the death to unlawfulness.

• The accused's own intoxication and actual foresight are not the question, so the drunk who hurls a stool into a packed bar is judged by the sober reasonable person there (Wilson). The risk is of serious injury, an appreciable one, not a certain or probable one (Holzer), so an expert who says a fatal outcome was vanishingly unlikely answers the wrong question. Keep the phrase distinct from the murder phrase, death or really serious injury, when both are left to the jury (Wilson).
• What the reasonable person is not given. Nothing personal to the accused that would affect his reasoning or his judgment of the danger is attributed. The reasonable person judges with the unclouded reasoning power of a healthy mind, so the accused's idiosyncrasies and his ephemeral emotional or mental state are excluded along with his intoxication (Wills). The accused's position and knowledge come in; his clouded head does not.

How dangerousness is fought on facts

• Position and knowledge. The reasonable person stands in the accused's position with the accused's knowledge (Wilson). A shove harmless to anyone else becomes dangerous where the accused knew the victim had just returned from brain surgery. Judging the act in the abstract is the wrong frame.
• Shock without contact. Terrifying a frail person with a known heart condition risks shock-based physical injury such as cardiac arrest, which can be serious injury, although emotional disturbance alone is not (Dawson; Vollmer). No touching is required.

Two further limits matter. The deeming covers a single punch or strike, so two punches in quick succession fall outside its terms and the ordinary Wilson test does the work, usually comfortably. And whenever the statutory route wobbles the common law test remains. Pain and disorientation is probably not an injury, and the strong move is naming that as a live issue rather than assuming it either way.

Negligent manslaughter

The duty gateway

Any one category grounds the duty, so argue the category that fits and move to breach.

• Relationship. The parent and child relationship carries the duty on its own: the father in Russell who stood by while his young children drowned was guilty of their manslaughter without any assumption of care (Russell). Domestic partners owe each other the same duty (Reid). State the relationship, cite the case, and move on.
• Assumption and seclusion. Carrying a helpless friend to a locked room and keeping the key takes her into exclusive custody and away from anyone else's aid. Partial help that secludes founds the duty rather than negates it (Taktak), and Instan shows assumption and reliance ground a duty even without positive care steps.
• Creation of the danger. A person who creates a danger and becomes aware of it must take the steps within their power to counteract it (Miller). Blocking a flue, later finding it blocked and doing nothing is the classic pattern.
• Where the categories run out. The counterexample is the drug supplier whose customer collapses in her presence. The High Court found no duty: the relationship of supplier and user lacks the element of control found in the relationships where the law imposes a duty to act, and the creation of danger route fails too, because the danger came from the victim's own act of taking the drug, not from the supply (Burns). Presence at the deterioration, without control, is not assumption.
• The stranger. No category reaches a stranger the accused neither assumed care of nor endangered, however the conduct is judged morally. Conclude firmly and briefly.

Breach: the great falling short

The most useful move is to name the act the duty required, such as the one phone call to the ambulance, then ask whether the failure to take it fell so far short of the reasonable standard as to merit criminal punishment (Nydam). Naming the required act exposes half measures. A jacket handed over and a door propped open do not answer a three hour failure to make the one call that mattered. Token gestures frame the gross breach rather than excuse it.

• The standard. The reasonable and unintoxicated person in the accused's position with the accused's knowledge (Lavender). An honest drunken belief that nothing was wrong is measured against the sober watcher who would have acted.
• Skilled roles raise the bar. Where the role demands special skill, the reasonable person holds it. A surgeon is measured against the reasonably competent surgeon, and special knowledge may raise the standard but never lowers it. The test stays wholly objective: the accused's subjective appreciation of the risk, and any insight he had or lacked into his own limitations, are irrelevant both to convict and to excuse (Patel).
• Attributes, not afflictions. The reasonable person shares the accused's attributes such as age and special knowledge and skills, in the circumstances the accused faced, but a concussed or dazed condition at the time is not attributed (Edwards). The accused judged through a fog is still measured against a clear head.
• The threshold cuts both ways. A momentary lapse while managing a competing danger, against a background of real care, is ordinary human fallibility rather than a great falling short. Weeks of escalating neglect against explicit warnings is the other end of the scale.
• The rational victim. Where a lucid adult who knows the risks emphatically refuses an ambulance, respecting the refusal while keeping watch is unlikely to merit criminal punishment, and a jury might be reluctant to find gross negligence proved. The refusal negates neither duty nor causation. It bears on breach, so put it there.

Causation by omission

• The prosecution need not prove the victim would certainly have lived. Evidence that a timely call gave a very good chance of survival across the decisive hours makes the omission a substantial contribution, and a defence demand for certainty applies the wrong test.
• Keep breach and causation separate. Evidence that an ambulance would very probably have saved the victim goes to causation and cannot manufacture a gross breach.

The selection is itself examinable. A paid carer who gives the prescribed sedative correctly, a lawful act, then leaves the client unattended in the bath commits no base offence, so UDAM fails at unlawfulness and negligent manslaughter is the available form. One clean sentence earns the selection marks.

How the examiners mark it

Manslaughter answers are marked on method as much as doctrine. Five habits separate strong answers.

• Elements first, then triage. Open with the element statement and its authority, then flag the live elements in one sentence. Causation and voluntariness will not be in dispute, and the contest is dangerousness. An obviously provable element gets one fact and one line. A doubtful one gets the analysis.
• Descend only on doubt. Run manslaughter only where the murder fault element is genuinely doubtful. An open and shut murder needs no manslaughter discussion. Where murder mens rea is unrealistic, address murder quickly and give the words to manslaughter.
• Conclude in likelihood language. The prosecution could probably prove the act was dangerous. A jury might be reluctant to find gross negligence proved. On genuinely arguable points the marks sit in the fact reasoning rather than the conclusion, and a well argued answer can land either way.
• Keep the fault lenses apart. Reckless murder asks what this accused actually foresaw as probable. Negligent manslaughter asks what a reasonable person in the accused's position would have appreciated. Subjective intention is relevant to murder and not to manslaughter (Patel), and sliding between the two lenses mid-answer is a defining error.
• Dismissal discipline. Kill the form that does not fit in one line rather than omitting it. There was no unlawful act, so the available form is negligent manslaughter.
• Keep the fallback alive. Where both forms wobble, usually on causation, drop to the offences against the person rather than leaving the accused unanalysed.

Critical pitfalls and counter-arguments

Take it to the practice bank

This module is drilled in the Criminal Law practice bank. Every problem there carries a realistic Pass answer, an H1 model answer, and an examiner's comment explaining the decisive fact and where the marks are lost.

Practice prompts

1. Take a fatal punch and work the base offence through its elements before calling the act unlawful.
2. State precisely what s 4A does and the three things it does not do.
3. Choose between the two forms of manslaughter on a set of facts and justify the choice.
4. Write the negligent manslaughter breach paragraph, naming the act the duty required.
5. Explain why the dangerousness test is objective while the base offence still carries its own fault.
6. Name the duty category for four one line scenarios and explain in one sentence why the drowning stranger case fails.
7. Write a causation by omission paragraph using very good chance evidence without demanding certainty of survival.
8. Argue dangerousness both ways where the accused knew a fact that made an otherwise ordinary act risky.