ABC v St George’s Healthcare NHS a duty to warn?

In this recent case the court considered whether a doctor has a legal duty to warn a patient’s offspring of a genetic risk without that patient’s consent.

In the recent case of ABC v St George’s Healthcare NHS (2015) (ABC) the court considered whether a doctor has a legal duty to warn a patient’s offspring of a genetic risk without that patient’s consent.

While the legal test for duty of care for healthcare professionals ultimately remains unaltered by the court’s judgment, the extent of such a duty must be considered as increasingly unclear. This is particularly evident when ABC is viewed against a backdrop of recent consent-related judgments, such as Montgomery v Lanarkshire Health Board, and the burgeoning development of genetic sequencing technology. This article summarises the judgment in ABC, examines whether the bar is likely to be set even higher for clinicians in terms of their duty to warn, and sets out some practical steps that clinicians can take when dealing with patients presenting with hereditary diseases. Please note that while we do not seek to promote the adoption of defensive practices or encourage the early extension of duties of care, it is reasonable to have regard to how the law in this area might develop, which is what this article seeks to address.

Consideration and judgment of the court

ABC concerned a claim brought by a patient's daughter, the claimant, against her father’s doctors, the defendants, for their failure to warn her of his Huntington’s disease, an inherited condition affecting certain nerve cells in the brain. The claimant’s father was diagnosed with the disease in November 2009, while the claimant was pregnant. The claimant’s daughter was born in April 2010 and in August 2010; the claimant was told accidentally about her father’s disease by one of his doctors. The claimant argued that the defendants’ failure to warn her caused her harm in the form of psychiatric damage, and (if her child also had the disease) the additional expense which she would have avoided by undergoing a test and had this been positive, terminating her pregnancy.

The High Court struck out the claim, because:

  1. Citing Caparo v Dickman, in order to impose liability for an omission, a special relationship between claimant and defendant is required. The circumstances in this novel situation could not be characterised in this way. The claimant argued that because she had attended multidisciplinary meetings in relation to her father’s care and she and her sister underwent family therapy with the defendants, a relevant duty of care was owed to her. However, the claimant could not point to any situation where a duty of care was recognised to exist which was at all comparable or close to the one presently recognised in law. However, giving us a glimpse into a future, the court said: “… of course, the categories of duty of care were not closed” (although it was added that they should be expanded only incrementally).
  2. The common law and GMC guidance recognise the confidential nature of information passing between doctor and patient by imposing a duty of confidence on the doctor. However, the court in ABC stated that this duty of confidence is not absolute, and that the public interest in preserving confidence could be outweighed by the public interest in disclosure (per Attorney-General v Guardian Newspapers). In this case, however, that was not deemed to make it fair, just or reasonable to impose a duty of care on the defendants.

Reiteration that clinician confidentiality is not absolute, combined with recognition that the categories of the duty of care remain open to challenge, leads to some questions. Namely, the circumstances in which a duty of confidence may be breached and the categories of duty of care expanded to create a binding duty to warn for healthcare professionals.

Ramifications of the decision

Although healthcare professionals and insurers should be assured by the judgment in ABC, it is wise to consider the thorny issues it raises.

For healthcare professionals, the decision serves to highlight the difficult and intertwined nature of informed consent, the duty of care and the principle of confidentiality. There has been a shift in judicial attitudes following Montgomery, which established that it is the doctor’s duty to take reasonable care to ensure that a patient is aware of any material risk involved in a treatment. The decision extended the law on causation on policy grounds and highlighted the importance of doctors ensuring that patients are equipped to give informed consent.

Practical steps that clinicians can take include discussing the genetic condition in detail and noting that they have offered to raise the issue with the patient’s relevant relatives. Of course, first and foremost a clinician’s duty of confidentiality and duty of care to their patient should remain their primary guiding principles, at least until further clarification is provided by the court on the concept of a duty to warn and this must remain at the forefront of a clinician’s mind. However, if the patient refuses to consent to disclose relevant information, the clinician should, in the first instance, take a good note of why consent is being refused. They should then consider contacting their indemnity provider medico legal helpline, the GMC or their clinical director to discuss the situation on an anonymous and confidential basis in order to seek more guidance as to whether, from a policy perspective, the information needs to be passed on irrespective of the patient’s viewpoint, and whether they might be deemed to owe a duty of care to a person who is not their patient, in order to ensure that this person is then capable of giving informed consent for any treatment that they may require.

From an insurance perspective, the decision in ABC is likely to result in more litigation as the extent of the duty to warn is tested. The burgeoning advance of ‘next generation’ genetic sequencing technology that allows the sequencing of large parts, or indeed all, of a patient’s genome will lead to more information being held by healthcare providers on individuals who are not their direct patients. Hence, there may be a duty to advise those non-patients of information which could impact on personal decisions, such as whether to have children. It is probable that in turn this will contribute to further challenges to the boundaries of the duty of care and indeed the evolution of a duty to warn.


Although ABC did not change the law in terms of the duty of care owed by a healthcare professional to a patient, it is clear that balancing the principles of patient confidentiality, informed consent, and the scope for the development of the boundaries of the duty of care is likely to become increasingly perplexing in practice. Added to this, the advance of genetic sequencing technology resulting in more information being held by healthcare professionals, means that English law is progressing ever closer to a duty to warn. As a result, healthcare professionals should demonstrate their consideration of and discussion about such issues in their notes, in order to show their engagement with the issues and their awareness that the knowledge they impart may have ramifications for individuals outside the usual patient/doctor relationship.

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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