H418/01 - Gross negligence manslaughter

An existing duty of care

Gross negligence manslaughter begins with a duty of care owed by the defendant to the person who dies.

It is an involuntary manslaughter offence: intention to kill or cause really serious harm is not required. Unlike unlawful act manslaughter, it need not be built on a positive criminal act. A normally lawful activity, such as treating a patient or maintaining equipment, can be performed with culpably bad negligence. A failure to act can also qualify where the defendant has a legal duty to act.

In R v Adomako (1994) an anaesthetist failed to notice a disconnection in the patient's oxygen supply during an operation. The patient died. The House of Lords confirmed the approach based on an existing duty, breach, causal death and negligence so bad, considering the risk of death, that it was criminal. Later decisions clarify the risk threshold; do not treat every fatal breach of a duty as enough.

Duties can arise from professional care, a contractual responsibility, a relevant relationship or an assumption of care. Creating or contributing to danger can also produce a duty to take reasonable steps once the life-threatening situation is, or should be, apparent. This is a legal obligation, not simply a moral expectation that everyone should rescue anyone in difficulty.

In R v Evans (2009) the defendant supplied heroin to her half-sister, recognised overdose signs and failed to obtain medical help. The Court of Appeal held that a person who creates or contributes to a danger which they know, or ought reasonably to know, has become life-threatening will normally owe a duty to take reasonable steps to save the other person's life. The duty did not depend merely on being a sibling. It followed from contribution to the danger and the relevant awareness. Seeking medical assistance can be the reasonable step; no unsupported duty to perform complex treatment is inferred.

Original comparison: A gas engineer undertaking a household boiler repair owes care to those exposed to the work. A passer-by who notices a remote emergency does not automatically acquire the same duty merely by witnessing it. If the passer-by has created the danger or assumed responsibility, the duty analysis may change. Identify the source and scope of the particular duty before discussing fault.

Breach and a serious risk of death

The defendant must breach the duty, and the breach must give rise to a serious and obvious risk of death which is reasonably foreseeable at that time.

Breach means falling below the standard expected of a reasonably competent person undertaking the relevant role. Medical or technical expertise can establish what reasonable care required. A duty may require monitoring, checking a dangerous connection or promptly calling for help. Being unsuccessful is not automatically being negligent: the actual conduct must fall below the appropriate standard.

The risk requirement is more demanding than unlawful act manslaughter's risk of some physical harm. Here the risk is of death, and must be serious and obvious. A remote possibility of a rare fatal condition is not necessarily serious; a hidden danger which might be discovered by a neglected investigation is not necessarily obvious. Also ask whether a reasonably prudent person undertaking the defendant's role would have foreseen that serious and obvious death risk. This is an objective assessment, made prospectively at the breach.

In R v Rose (2017) an optometrist's failure properly to examine a child's eyes was followed by the child's death from an undetected condition. The Court of Appeal quashed the conviction. Foreseeability could not be established by giving the defendant the information which the omitted examination would have revealed. The assessment had to use the circumstances at the breach, rather than hindsight. The decision does not say omitted examinations can never support liability: existing clear warning signs may establish a serious and obvious death risk.

Original comparison: A care worker sees a dependent resident unconscious, blue and struggling to breathe, but ignores repeated requests to call emergency help. The signs strongly support a present obvious and serious death risk. Compare a routine appointment with no apparent life-threatening warning signs, where an omitted check would have revealed a rare hidden condition. The omitted check may be negligent, but Rose warns against using its unmade discovery to satisfy the risk threshold retrospectively.

The breach must cause death

Even a dreadful breach must be a sufficiently significant cause of the death for this homicide offence.

Factual causation asks whether the person would have died as and when they did but for the breach. Legal causation requires a significant contribution; the breach need not be the only cause. A pre-existing illness can operate alongside negligent care. The prosecution still must make the jury sure that the particular breach contributed in the required way.

Omission cases need a careful counterfactual: what difference would the required action have made? If a defendant fails to call for help, medical evidence about the effect of timely help is necessary. An opportunity to help is not automatically proof that the omission caused death. If the evidence leaves reasonable doubt whether proper action would have prevented the relevant death, the prosecution cannot simply replace proof of causation with the defendant's bad behaviour.

R v Misra and Srivastava (2004) concerned doctors' failures in caring for a patient who died from infection. The Court of Appeal approved directions requiring the prosecution to establish causation: once the patient's condition was irreversible, a subsequent failure could not be treated as causing that death. The decision therefore illustrates both culpably poor care and the need to locate the causative breach. It does not create a rule that doctors are liable whenever a patient dies under their care.

Original application: Sam owes a duty to an injured climber and sees signs of a fatal emergency. If prompt help would have saved the climber and Sam's failure materially causes death, causation is supported. If experts cannot exclude that the climber would have died at the same time despite prompt help, that doubt matters. If earlier neglect made the condition irreversible, examine that earlier breach rather than assuming all later neglect has the same causal effect.

Medical uncertainty about causation is different from uncertainty about grossness. Causation concerns whether the breach brought about the death; grossness concerns how culpable the breach was. A highly culpable omission with no proved causal contribution cannot establish manslaughter by this route, even though other offences or professional consequences may remain.

Grossness and objective fault

The jury must be sure that the breach was so exceptionally bad in all the circumstances that it warrants criminal punishment as manslaughter.

This is more than ordinary negligence, and more than labelling a mistake “serious”. Adomako makes grossness a judgment for the jury, considering the risk of death and the circumstances. R v Sellu (2016) emphasises the high threshold: the jury must understand the distinction between serious or very serious mistakes and conduct which is truly exceptionally bad. Expert evidence helps identify the expected standard and departure from it; an expert does not replace the jury's judgment of criminal grossness.

The jury can consider the magnitude and duration of the failure, obvious warnings, opportunities to correct it, the defendant's responsibilities and the situation in which the defendant acted. Evidence of severe pressure, inadequate support or genuine attempts to obtain help can matter. None of those facts creates an automatic acquittal; equally, a bad outcome is not proof of gross negligence. A supported conclusion explains why the departure reaches, or may fail to reach, the criminal threshold.

There is no separate requirement to prove subjective recklessness. In Attorney General's Reference (No 2 of 1999) (2000) the Court of Appeal confirmed that the Adomako test is objective. The defendant need not actually have appreciated the death risk for liability. Their state of mind can nevertheless be relevant to grossness: deliberately ignoring a known warning may be particularly culpable, while a genuine lack of awareness can form part of the circumstances. It does not automatically excuse an objectively gross breach.

This offence therefore involves fault through gross negligence, rather than murder's intention or a requirement of conscious risk-taking. Calling it “strict liability because intent is absent” is misleading: the prosecution must prove a culpable breach, serious and obvious foreseeable death risk, causal death and grossness. Nor should tort's ordinary compensation threshold be copied into criminal liability. The related duty-and-breach vocabulary supplies a synoptic connection, but the criminal threshold and prosecution burden are distinct.

Original application: An experienced engineer ignores repeated clear carbon-monoxide warnings, leaves an unsafe boiler operating and a resident dies because of that breach. The warnings and repeated opportunities support grossness. Compare an engineer taking reasonable safety steps under an unexpected equipment failure: the outcome alone does not establish a breach, much less grossness. Even in the first case, each element needs proof before a verdict is justified.

The flexibility of grossness allows a jury to weigh real working circumstances, but the degree judgment can make outcomes less predictable. Requiring a very high threshold and clear judicial directions protects against criminalising ordinary error. A developed analysis links that safeguard to the risk of death and the distinction between compensation and criminal punishment, while acknowledging that it does not produce a numerical dividing line.

Quick recap

Find an existing duty, breach, serious and obvious foreseeable death risk, causal death and criminal grossness. Assess the risk at the breach and the negligence in its real circumstances; death alone proves none of these steps.