When is a risk material? Examining the impact of Montgomery v Lanarkshire Health Board

Nearly two years after the Supreme Court’s ruling in Montgomery v Lanarkshire Health Board , can we now confidently wave goodbye to the “responsible body of medical opinion” and hello to the “reasonable patient” where material risks are concerned?

The facts and decision in Montgomery are well known. The Claimant, a pregnant diabetic, was not informed of a 10 per cent risk of shoulder dystocia during birth and a 0.1 per cent risk that as a result of complications, her baby would suffer from cerebral palsy or death, the former of which regrettably occurred.

In a departure from the “responsible body of medical opinion” threshold developed in Sidaway, the Supreme Court ruled that the doctor’s duty was to:

“.. take reasonable care to ensure that the patient is aware of any material risks involved in the recommended treatment and any reasonable alternative or variant treatments”.

Life post-Montgomery

The change in approach was welcomed by medical and legal professionals. It was felt to reflect the realities of clinical practice and supported GMC guidance on consent. Some however worried it represented a more significant change in approach and risked greater disputes over what constituted a “material” risk and therefore “informed” consent.

The decision has attracted attention. A number of judgments have emerged which not only apply the decision but seek to test its limits.

Testing the limits

Perhaps of most interest to those worried by the potential reach of Montgomery is the decision in Shaw v Kovak. The Claimant brought a claim on behalf of her late father who had died following an operation for a transaortic valve implant (TAVI). The Claimant sought to argue that Montgomery established an entirely separate cause of action, unrelated to a claim for damages for personal injury or loss of expectation of life. She argued that where there had been a negligent non-disclosure of information by a doctor, a claim for damages for the “removal of the right to make an informed choice as to treatment” could arise.

The Court was not persuaded. His Honour Judge Platts confirmed the decision in Montgomery:

"…informs the issue of whether or not there is a breach of duty of care against what standard is the action of the doctor to be judged"

but goes no further.

Similarly, the Courts are keen to ensure that the right to be informed remains limited to the material risks and any reasonable alternative treatments. Thus in Tasmin v Barts Health NHS Trust the Court held that foetal blood sampling at the time contended would have revealed only a negligible and immaterial risk of a hypoxic/ischaemic insult occurring. As a result, the risk did not fall within the category intended to be caught by Montgomery and the registrar was not at fault for failing to advise of it. Although a percentage figure was discussed, Mr Justice Jay confirmed that the decision was based on a risk classified as being “too low to be material” as opposed to any numerical assessment.

Application beyond the clinical negligence sphere?

While the Court was not prepared in Kovak to go as far as to create a new cause of action, it is clear that Montgomery is not a decision that will be limited to the clinical negligence sphere alone.

In Baird v Hastings, a Northern Irish Court of Appeal judgment from May 2015, the Claimant brought proceedings against her former solicitor for negligence and breach of contract. Finding in favour of the Claimant, the Court held that the scope of the solicitor’s duty to advise was akin to that of the medical professional as per Montgomery. Thus:

"The doctor/patient relationship is not a full or true analogue of a solicitor/client relationship since the therapeutic duties owed by a doctor to a patient raises different questions from those arising between a solicitor and client. However, a solicitor is bound to take reasonable care to ensure that the client understands the material legal risks that arise in any transaction which the client has asked the solicitor to handle on his behalf. As in the doctor/patient relationships the test of materiality is whether a reasonable client would be likely to attach significant to the risks arising which should be reasonably foreseeable to the competent solicitor. As in the medical context, the advisory role of the solicitor must involve proper communication and dialogue with the client".

Having made that finding, the Court proceeded to refer the matter back to the trial judge to determine the issue of causation. It therefore remains to be seen what the Court will consider a "material" legal risk in the context of the Claimant’s conveyancing transaction.

The guidance in Baird has since been applied by the High Court in the decision of O’Hare and another v Coutts & Co. In finding that Coutts had breached its duty to exercise reasonable skill and care in providing investment advice, the Court held that there was a need to place an increased focus on whether or not clients are informed of material risks involved such that they can make their own decisions about whether or not to proceed to invest. This was particularly so in the context of an industry where there was a lack of consensus as to acceptable market practice.

Looking to the future

The application of Montgomery in the time since the Supreme Court’s decision appears fair. While those defending professional negligence claims in all spheres can breathe a sigh of relief at the decision in Kovac not to allow a free-standing cause of action, the wider application of the principles in Baird and O’Hare highlight the need for all professionals to be conscious of the need to ensure material risks and reasonable alternatives are discussed with patients/clients alike.

Assuming they do so, it should, in theory, become easier to assert that the fully informed client should have to bear responsibility for those risks that they do assume. The difficulty, we suspect, will come in finding the time in an already stretched practice to have the in-depth discussions on risk now required.

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