Revision Hub / Module 1 · The Negligence Chain

Breach of Duty

Lecture L3 Compulsory in Part I Reading: Horsey & Rackley ch 8; Nolan & Oliphant ch 4

Snapshot

Breach is the second link in the negligence chain. Once duty is established, the question is whether the defendant fell below the standard of care. The inquiry has two stages: identifying the standard (law) and asking whether conduct fell below it (fact). The standard is overwhelmingly objective. Strong answers identify the standard, deploy the four Bolton v Stone factors with explicit weighing, and adapt the inquiry where the defendant is a child, professional, or unaware of a disabling condition.

1. The standard: the reasonable person

The classic formulation comes from Alderson B in Blyth. It frames breach as either careless action or careless omission, judged against a hypothetical prudent person.

Blyth v Birmingham Waterworks Co (1856) 11 Exch 781

Facts: A water main fractured during an unusually severe frost, flooding the claimant's house.
Holding: No breach; the defendants had taken the precautions a reasonable person would have taken.
Principle: Negligence is omitting what a reasonable person would do, or doing what a prudent person would not — the canonical definition of breach.

The reasonable person is deliberately impersonal — "the man on the Clapham omnibus" (Hall v Brooklands Auto-Racing Club [1933] 1 KB 205); neither saint nor fool. He is not the defendant: Glasgow Corporation v Muir [1943] AC 448. The defendant's honest belief and good intentions are irrelevant.

Vaughan v Menlove (1837) 3 Bing NC 468

Facts: The defendant built a hayrick despite repeated warnings of fire risk, saying he "would chance it"; it ignited and destroyed the claimant's cottages.
Holding: Liable; acting "bona fide to the best of his judgment" was no defence — the standard is that of ordinary prudence, judged objectively.
Principle: The foundational rejection of a subjective standard of care.

The standard is one of foresight, not hindsight: a defendant is judged on what was reasonably knowable at the time.

Roe v Minister of Health [1954] 2 QB 66

Facts: Patients were paralysed after anaesthetic ampoules were stored in phenol that seeped through invisible cracks in the glass.
Holding: No breach; the risk was unknown to medical science at the time.
Principle: Per Denning LJ: "we must not look at the 1947 accident with 1954 spectacles."

2. Variations of the standard

The objective test is calibrated to the activity and to certain personal characteristics: children, learners, professionals, DIY defendants, contextual amateurs, and those rendered incapable by sudden disability.

Children

A child defendant is judged by the standard of an ordinarily prudent child of the same age, not the adult standard.

Mullin v Richards [1998] 1 WLR 1304 (CA)

Facts: Two 15-year-olds play-fighting with plastic rulers; a fragment blinded the claimant.
Holding: No breach; the risk was not one a reasonable 15-year-old would have foreseen.
Principle: Age-adjusted standard for child defendants. Orchard v Lee [2009] EWCA Civ 295 adds that ordinary boisterous behaviour is rarely careless without more.

Learners

The law refuses to lower the standard for adult learners performing activities open to the public — third parties cannot be expected to inquire whether the driver is a novice, and insurance distributes the loss.

Nettleship v Weston [1971] 2 QB 691 (CA)

Facts: A learner driver crashed during her third lesson, breaking the instructor's kneecap.
Holding: The learner owes the same standard as a qualified driver; any other rule would yield, per Lord Denning, "endless confusion and injustice".
Principle: The standard is fixed by the activity, not the actor. Same logic for inexperienced junior doctors: Wilsher v Essex AHA [1987] QB 730.

The "DIY" defendant and the contextual amateur

An amateur undertaking work normally done by a tradesman is judged by the standard of a reasonably competent amateur performing the same task.

Wells v Cooper [1958] 2 QB 265 (CA)

Facts: The defendant, a competent amateur carpenter, fitted a door handle that came away in the claimant's hand, causing injury.
Holding: No breach; the screws used were adequate by the standard of a reasonably competent householder, not a professional joiner.
Principle: The standard is calibrated to the job a reasonable person would undertake themselves; tasks plainly requiring professional skill cannot be DIY'd.

Where a service-provider holds themselves out only as a non-specialist, the law expects only the skill of that non-specialist.

Phillips v William Whiteley Ltd [1938] 1 All ER 566

Facts: A jeweller pierced the claimant's ears; she developed an abscess and serious infection.
Holding: No breach; the jeweller need only take the precautions of a reasonably competent jeweller, not a surgeon.
Principle: Defendants are measured against the activity they are performing in the role they have assumed.

Sudden disability

Where the defendant is incapacitated by a condition of which they neither knew nor could reasonably have known, the standard is suppressed to that of a reasonable person unaware of the condition.

Mansfield v Weetabix Ltd [1998] 1 WLR 1263 (CA)

Facts: A lorry driver blacked out from undiagnosed malignant insulinoma and crashed into the claimant's shop.
Holding: No breach; he could not reasonably have known of the condition.
Principle: Distinguished Roberts v Ramsbottom [1980] 1 WLR 823, where the defendant was on notice of warning symptoms; Mansfield applies only to genuine, non-negligent unawareness.

Emergencies and rescue contexts are treated similarly (Das v Manley [2002] EWCA Civ 1638), and sport participants are judged by reckless-disregard rather than the orthodox test (Wooldridge v Sumner [1963] 2 QB 43).

3. Risk-balancing: the four Bolton v Stone factors

Once the standard is identified, the court balances four factors. This is sometimes captured in the Learned Hand formula (B < PL): United States v Carroll Towing 159 F 2d 169 (1947); reflected in Lord Reid's reasoning in The Wagon Mound (No 2) [1967] 1 AC 617.

(a) Probability of harm

Bolton v Stone [1951] AC 850 (HL)

Facts: The claimant was struck by a cricket ball driven from a ground; balls had been hit out only six times in 28 years over a 17-foot fence 78 yards from the batsman.
Holding: No breach; the risk was small and well-guarded.
Principle: The lower the chance of harm, the less is required by way of precaution. Compare Haley v London Electricity Board [1965] AC 778 (foreseeable blind pedestrians demanded greater warnings).

(b) Gravity of harm

Even a low-probability risk may demand precaution where the magnitude of harm is high, especially given a known vulnerability.

Paris v Stepney Borough Council [1951] AC 367 (HL)

Facts: A one-eyed mechanic lost the sight of his good eye when a splinter struck him; his employer had not provided goggles, although trade practice did not require them for two-eyed workers.
Holding: Breach; the grave consequence to this claimant — total blindness — required goggles even if not for others.
Principle: The reasonable person's response is sensitive to severity for the claimant in question.

(c) Practicability and cost of precautions

Latimer v AEC Ltd [1953] AC 643 (HL)

Facts: An exceptional storm flooded the factory; the defendant spread all available sawdust but the claimant slipped. Closing the factory would have eliminated the risk.
Holding: No breach; spreading sawdust and warning workers was proportionate, shutting down was not.
Principle: The court does not require precautions whose cost would be wholly disproportionate to the risk.

(d) Utility / social value of the conduct

Where the activity is socially valuable (notably emergency response), courts tolerate greater inherent risks.

Watt v Hertfordshire County Council [1954] 1 WLR 835 (CA)

Facts: A fireman was injured when a heavy jack, loaded onto a non-specialist lorry to reach a trapped victim, slid in transit.
Holding: No breach; per Denning LJ, "if all the trouble of saving life and limb were taken away, you would not have made it possible at all".
Principle: Social utility justifies risks unjustifiable in commercial contexts. Reinforced by s 1 Compensation Act 2006 and SARAH 2015, directing courts to consider whether a precaution would deter desirable activities.

(e) Common practice

Conformity with industry practice is strong (not conclusive) evidence of meeting the standard; departure is strong evidence of breach. The court retains the final word: an unreasonable common practice will not save the defendant. See Ng Chun Pui v Lee Chuen Tat [1988] RTR 298 (a res ipsa case below).

When applying the Bolton v Stone factors, do not list — weigh: high gravity may eclipse low probability (Paris); low practicability may mean a foreseeable risk does not require closure (Latimer); high utility may justify what would otherwise be unjustifiable (Watt). The explicit weighing earns the marks.

4. Professional standard: Bolam, Bolitho, Montgomery

Where the defendant exercises a profession or special skill, the standard is that of the ordinary skilled person exercising that skill. The classic test is Bolam, refined by Bolitho and reshaped on informed consent by Montgomery.

Bolam v Friern Hospital Management Committee [1957] 1 WLR 582

Facts: The claimant suffered a fractured pelvis during ECT given without muscle relaxants; medical opinion was divided on the right protocol.
Holding: No breach; a doctor is not negligent if he acts in accordance with a practice accepted as proper by a responsible body of medical opinion.
Principle: Professional standards are set by the profession itself, provided a "responsible body" supports the conduct.

Bolitho v City and Hackney Health Authority [1998] AC 232 (HL)

Facts: A two-year-old died of cardiac arrest after a doctor failed to attend; experts disagreed on whether intubation would have been appropriate.
Holding: Bolam reaffirmed but qualified: the body of opinion must be "capable of withstanding logical analysis".
Principle: The "Bolitho gloss". Per Lord Browne-Wilkinson, this will be unusual: in most cases expert disagreement leaves Bolam intact.

Montgomery v Lanarkshire Health Board [2015] UKSC 11

Facts: A diabetic mother of small stature was not warned of the 9–10% risk of shoulder dystocia in vaginal delivery; the baby was severely injured.
Holding: Breach. What risks to disclose is not a clinical-judgment matter governed by Bolam; the doctor must take reasonable care to inform the patient of any material risk and of reasonable alternatives.
Principle: A patient-centred test, replacing the doctor-centred Sidaway [1985] AC 871 approach. A risk is "material" if a reasonable patient would attach significance to it, or the doctor knew this patient would. Duce [2018] EWCA Civ 1307 sets a two-stage test; on alternative treatments, McCulloch v Forth Valley Health Board [2023] UKSC 26 reverted to a Bolam-style enquiry.

5. Proof of breach: res ipsa loquitur

The burden of proving breach rests on the claimant on the balance of probabilities. Where the claimant cannot reconstruct the precise mechanism but can show the accident is one which would not ordinarily happen without negligence, res ipsa loquitur permits inference of breach in the absence of explanation.

Scott v London & St Katherine Docks Co (1865) 3 H&C 596

Facts: A customs officer was struck by six bags of sugar that fell from a crane operated by the defendants.
Holding: Liable; Erle CJ identified three conditions: management by the defendant; an accident not ordinary without lack of proper care; no inconsistent explanation.
Principle: The doctrine permits an inference of breach from the fact of the accident itself.

Res ipsa does not reverse the legal burden: Ng Chun Pui v Lee Chuen Tat [1988] RTR 298 (coach inexplicably crossed a central reservation) confirms it gives only an evidential inference; if the defendant offers a plausible non-negligent explanation, the claimant must still discharge the legal burden.

6. Application framework

Identify the standard of care. Begin from the objective reasonable person (Blyth; Vaughan v Menlove). Adjust for: child (Mullin v Richards), professional (Bolam), DIY/amateur context (Wells v Cooper; Phillips v Whiteley), or sudden, unknown disability (Mansfield v Weetabix). State the resulting standard explicitly.
Apply foresight, not hindsight. Anchor to what was reasonably knowable at the time (Roe v Minister of Health).
Run the risk-balancing factors. Probability (Bolton v Stone); gravity (Paris v Stepney); cost and practicability (Latimer v AEC); social utility (Watt v Hertfordshire; Compensation Act 2006 s 1; SARAH 2015). Reference common practice as evidence (Ng Chun Pui) — not conclusive.
Weigh and conclude. State which factor dominates and reach a conclusion on whether conduct fell below the standard.
Consider proof. If facts are opaque but the accident is one not normally occurring without negligence, flag res ipsa loquitur (Scott; Ng Chun Pui) — the burden stays on the claimant.

7. Common pitfalls

Treating breach as moral fault. The standard is impersonal: a defendant who tried her best can still breach (Vaughan v Menlove; Nettleship v Weston). Avoid "but she didn't mean to" reasoning.

Listing the Bolton v Stone factors without weighing them. Marks lie in articulating the tension on the facts. A bullet-list that picks no winner is a 2:2 answer.

Confusing Bolam with the universal test. It applies only to professionals exercising special skill, no longer governs informed consent (Montgomery), and post-Bolitho does not evade logical scrutiny.

Forgetting Roe v Minister of Health. Anchor the standard to knowledge available at the time of the conduct — not at the date of trial.

8. Exam checklist

Stated the objective standard with Blyth and Vaughan v Menlove.
Identified any variation of the standard (child / learner / professional / DIY / disability).
Anchored the inquiry to what was reasonably knowable at the time (Roe).
Applied all four Bolton v Stone factors and weighed them on the facts.
Cited Watt v Hertfordshire / Compensation Act 2006 s 1 where social utility is engaged.
Where a professional is involved, applied Bolam with the Bolitho qualification; deployed Montgomery if consent or risk-disclosure is in issue.
Considered whether res ipsa loquitur assists the claimant, and noted the burden does not shift.
Reached a clear conclusion on whether the conduct fell below the identified standard.