This guide is maintained as a current resource for August 2026 and covers only the laws of England and Wales. Information is for general guidance, not legal advice. Consult a qualified solicitor for advice specific to your situation.
A detailed guide to how breach of duty is determined in clinical negligence claims in England and Wales. Learn how courts apply the Bolam, Bolitho and Montgomery tests to assess whether healthcare professionals have met the legal standard of care, with expert evidence, consent standards and practical examples explained.
In clinical negligence law in England and Wales, establishing breach of duty is central to a successful claim for compensation. Breach of duty determines whether a healthcare provider has failed to meet the legal standard of care owed to a patient, causing avoidable harm. This article explains how courts and tribunals assess breach of duty in clinical negligence claims, including the legal tests, relevant case law, practical examples, and considerations for claimants. Information is drawn from authoritative UK sources and legal principles to ensure accuracy and clarity for both non‑experts and solicitors.
Introduction
A clinical negligence claim arises when a patient alleges that a healthcare professional, NHS trust, private clinic or other clinical provider breached the duty of care owed to them, and that breach caused injury, loss or harm. A breach of duty means the healthcare provider's conduct fell below the standard of care expected under English and Welsh law. The standard and legal tests applied reflect the complexity of healthcare practice and aim to balance professional discretion with patient safety.
What Breach of Duty Means in Clinical Negligence
Under English tort law, a breach of duty occurs when a defendant's conduct falls short of the standard expected in the circumstances. In clinical negligence, this standard is not judged by hindsight or outcome alone, but by comparing the healthcare professional's actions with what could reasonably be expected of a competent practitioner in the same field and situation.
In other words, a breach means the clinician did not exercise reasonable skill and care consistent with professional standards, such that the conduct objectively departed from what competent professionals would do.
The Traditional Standard: The Bolam Test
The Bolam Principle
The foundational legal test for breach of duty in clinical negligence is the Bolam test, established in Bolam v Friern Hospital Management Committee [1957]. Under this test, a healthcare professional is not negligent if they acted in accordance with a practice accepted as proper by a responsible body of medical professionals with relevant expertise. This acknowledges that medicine often involves genuine differences of opinion among competent practitioners.
This means that the claimant must show the clinician's conduct was not supported by any reasonable body of professional opinion; it is not enough that other clinicians might have acted differently.
Interpretation in Practice
For example, if a surgeon chooses one acceptable surgical technique over another, and a responsible body of surgeons supports that approach, there is generally no breach even if another professional would have chosen an alternative. The Bolam test focuses on acceptable practice rather than best practice.
Refinement by Bolitho: Court Scrutiny of Expert Opinion
The Bolam test was refined by the House of Lords in Bolitho v City and Hackney Health Authority [1997]. Bolitho introduced a necessary qualification: expert medical opinion relied upon must be capable of withstanding logical analysis. Simply asserting a professional view is not sufficient if that view cannot be logically justified in the circumstances.
In practical terms, the court will examine whether the professional opinion identifying no breach is reasonable and defensible. If the expert evidence lacks logical foundation, the court may reject it and find the clinician in breach. This places an objective check on otherwise subjective professional opinions.
Informed Consent and the Shift After Montgomery
A significant development in clinical negligence law affected how breach of duty is assessed in relation to informed consent. In Montgomery v Lanarkshire Health Board [2015] UKSC 11, the Supreme Court departed from Bolam for risk disclosure. The court held that clinicians have a duty to take reasonable care to ensure that patients are aware of material risks inherent in a proposed treatment and of reasonable alternatives.
Under Montgomery, the standard for breach in consent cases is not whether a responsible body of medical opinion would have disclosed certain risks, but whether a reasonable person in the patient's position would attach significance to those risks. The clinician must also consider the specific patient's circumstances where known.
This represents a shift toward a more patient‑centred standard for consent, while Bolam/Bolitho continues to apply to technical aspects of diagnosis and treatment decisions.
Applying the Tests: Practical Context
Clinical Decisions and Treatment
When assessing technical clinical decisions (such as diagnostic choices, surgical procedures or treatment plans), courts still apply the Bolam‑Bolitho framework. The claimant's legal representative typically obtains independent expert reports from clinicians in the same specialty to explain accepted practice. The court then compares the defendant's conduct with these professional standards and examines whether expert opinion withstands logical analysis.
Risk Disclosure and Consent
For informed consent issues, the court applies the Montgomery principles. If a clinician did not disclose a material risk that a reasonable patient would want to know, this may constitute a breach of duty regardless of professional opinion to the contrary.
For example, not explaining significant risks of a common surgical procedure which might affect decision‑making has been held to breach the duty to inform.
Evidence in Proving Breach of Duty
Expert Witness Evidence
Expert medical evidence is central to determining breach of duty. Experts explain accepted standards, justify professional practices, and assist courts in evaluating whether the clinician's conduct met those standards. However, expert opinion is not determinative; the judge may accept or reject it based on logical reasoning under Bolitho.
Documentary Evidence
Medical records, treatment notes, consent forms, referrals and correspondence provide factual context for clinician conduct. These documents, combined with expert analysis, help establish whether the standard of care was met or breached.
Common Misunderstandings
Breach vs Bad Outcome
A common misconception is that any adverse clinical outcome is evidence of breach. In fact, a poor outcome does not itself show a departure from acceptable practice. There must be evidence the clinician's conduct objectively fell below the standard reasonably expected.
Multiple Practices vs Logical Foundation
That there are differing professional views does not automatically imply a breach. As long as a responsible body of clinical opinion supports the practice and the opinion is logically defensible under Bolitho, there is typically no breach.
Time Limits and Legal Process
Clinical negligence claims must generally be started within three years of the date of the breach or from date of knowledge (when the claimant first realised harm was linked to negligence). This is governed by the Limitation Act 1980. Claimants should seek legal advice early to ensure compliance with time limits and to commence evidence gathering promptly.
Key Takeaways
Breach of duty in clinical negligence in England and Wales is determined by comparing a clinician's conduct against the standard of care reasonably expected in similar circumstances. The Bolam test, refined by Bolitho, assesses whether the care provided is supported by responsible professional opinion capable of logical justification. For informed consent, Montgomery established a patient‑centred standard requiring disclosure of material risks. Expert evidence and logical analysis play key roles in assessing breach, while adverse outcomes alone do not prove substandard care. Understanding these legal tests aids claimants and solicitors in evaluating potential clinical negligence claims.
