Medical Negligence in English Law

Introduction

Medical negligence is the branch of tort law that governs claims for compensation arising from substandard medical treatment. A claim in medical negligence requires the claimant to establish that the defendant healthcare professional owed a duty of care, breached that duty by falling below the required standard of care, and caused the claimant damage. The law has developed significantly in recent decades, particularly in relation to the standard of care for diagnosis and treatment (the Bolam test) and the duty to warn of risks (the Montgomery test).

The Bolam Test

The standard of care in medical negligence claims is governed by the Bolam test, derived from Bolam v Friern Hospital Management Committee (1957). McNair J directed the jury that a doctor is not guilty of negligence if they have acted in accordance with a practice accepted as proper by a responsible body of medical opinion, even though other doctors would have adopted a different practice.

The Bolam test requires the court to determine whether the defendant’s conduct fell below the standard of a reasonably competent practitioner in the relevant field. The test is objective and is applied by reference to professional opinion. The defendant is not negligent if they acted in accordance with a practice accepted as proper by a responsible body of medical opinion, even if that body is a minority.

The Bolitho Gloss

The Bolitho gloss (from Bolitho v City and Hackney Health Authority (1998)) qualifies the Bolam test. The House of Lords held that the court is not bound to accept a body of professional opinion simply because it exists. The court must be satisfied that the professional opinion has a logical basis — that the expert evidence is capable of withstanding logical analysis.

If a body of professional opinion is not capable of withstanding logical analysis — if it is irrational, illogical, or fails to take account of relevant considerations — the court may reject it and find the defendant negligent. The Bolitho gloss enables the court to scrutinise professional opinion and to reject opinions that are not logically defensible.

The Montgomery Test for Informed Consent

The duty to warn of risks was fundamentally reformed by Montgomery v Lanarkshire Health Board (2015). The Supreme Court held that the Bolam test does not apply to the duty to disclose risks to patients. Instead, the court adopted a patient-centred test: a doctor is under a duty to take reasonable care to ensure that the patient is aware of any material risks involved in any recommended treatment, and of any reasonable alternative or variant treatments.

A risk is material if a reasonable person in the patient’s position would be likely to attach significance to it, or if the doctor is or should reasonably be aware that the particular patient would be likely to attach significance to it. The test focuses on what the patient would consider significant, not on what a responsible body of medical opinion considers appropriate to disclose.

The duty extends to informing the patient of alternative treatments, including the option of non-treatment. The doctor must engage in a dialogue with the patient to enable them to make an informed decision about their treatment.

Causation

The claimant must prove that the defendant’s breach of duty caused the damage. Causation has two elements: factual causation (the “but for” test) and legal causation (remoteness).

In medical negligence cases, factual causation is often the most difficult element. The claimant must prove that, but for the defendant’s breach, the damage would not have occurred. In Chester v Afshar (2004), the House of Lords held that a surgeon who failed to warn a patient of the risk of a rare complication was liable for the injury that materialised, even though the patient could not prove that she would not have had the surgery if she had been warned.

The Material Contribution Test

Where there are multiple potential causes of the damage and the medical evidence cannot establish which was the operative cause, the court may apply the material contribution test. In Bonnington Castings Ltd v Wardlaw (1956), the House of Lords held that the claimant need only prove that the defendant’s breach made a material contribution to the injury, not that it was the sole cause.

The material contribution test has been applied in cases of clinical negligence where there are multiple independent causes and the medical evidence cannot establish the precise causal mechanism.

Loss of Chance

In medical negligence cases involving diagnosis, the claimant may claim for loss of chance — the loss of the opportunity of a better medical outcome. The claimant must prove that the defendant’s breach caused the loss of a substantial chance of a better outcome. The value of the claim is assessed by reference to the percentage chance lost.

Conclusion

Medical negligence in English law has evolved significantly, with the Montgomery test replacing the Bolam test for informed consent and the courts adopting a more rigorous approach to the assessment of professional opinion. The patient-centred approach to consent, the rigorous scrutiny of expert evidence, and the flexible approach to causation ensure that patients can obtain compensation for substandard medical treatment while protecting clinicians from unjustified claims.