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M'Naghten rules and civil cases - Dr Mark Burgin

26/07/21. Dr Mark Burgin BM BCh (oxon) MRCGP discusses how the M'Naghten rules which are for criminal cases shine a light upon areas of injustice in civil cases particularly clinical negligence.

The M'Naghten rules are used in criminal cases to consider whether a person is not guilty of the crime by reason of insanity. The wording includes to ‘not to know the nature and quality of the act’ and this raises an interesting question. Can conditions such as autism or depression be considered as detects of mind – the answer is yes. There is no assessment of whether these claimants understand the nature and quality of the clinical error. This means that many litigants in civil cases will also suffer unfairness but they have no protection in law.

In clinical negligence observations suggest that even the experts can struggle to understand the nature and quality of the act. Although the points made could apply to any claimant, they cause particular injustice on those who suffer from a defect of mind. Most claimants who are neurodifferent or have depression are presumed to have capacity. They do still have functional restrictions such as rigidity of thought that even the best legal advice cannot resolve. Some lawyers override their clients using best interest reasoning, but this is strictly forbidden.

There are three situations where a lawyer could potentially challenge the standard practice using the reasoning in M'Naghten. The first relates to limitation where a person with a defect of mind could be out of time without ever having suspected that anything went wrong. The second is where the claimant is suspicious but does not have knowledge of the nature and quality of what happened. The third is where they are told what happened but cannot understand what they are told.


In limitation cases the clock does not start until the claimant reaches maturity and never starts in those without capacity. This approach is unfair for the majority of claimants who could not possibly understand the nature and quality of what happened because it is too complex. Often the hospital’s own investigation fails to understand what went wrong. How much more unfair is limitation on those who were severely injured who quite reasonably were focused on recovery rather than litigation.

Limitation assumes (incorrectly) that wronged party was in a position to make a claim immediately after the wrong. Whilst this is true for most civil cases it is patently untrue for many clinical negligence cases. Where a potential claimant was told by their treating physicians that nothing had gone wrong and it was just unfortunate the claimant simply cannot have knowledge. How are they expected to know better than their treating physicians? There is no suggestion that the treating physicians have been dishonest just that they did not themselves know of the mistake.

More concerning is the situation where the potential claimant has a defect of mind. Application of limitation in these cases can put a wholly unfair burden by asking them to deal with the effects of the injury including any psychological effects, to work out what happened even if their treating physicians did not, ask a legal advisor to investigate the situation without a clear idea of what the case is. This asks too much of a reasonable person and asks the impossible of those whose mind is not reasonable.

Nature And Quality of The Act

Clinical negligence experts are often struck by the observation that the claimant’s ideas about what went wrong are often fanciful. Their descriptions are medically implausible, not supported by the evidence and border on delusional. That is not to say that they are wrong in saying that there was a mistake, this sadly all too often is easy to prove. It is simply that they do not understand the nature and quality of the mistake. Until a neutral and thorough investigation is carried out (Stage 2 screening report) the claimant cannot know what has happened.

The defendants will argue that the claimant was suspicious and therefore had knowledge earlier. This is disingenuous as the claimant may well find it difficult to persuade a lawyer to take on the case if they cannot explain the error. The converse argument demonstrates the weakness to this argument, if suspicion is knowledge then claimants can gain knowledge by suffering from paranoia. As the saying goes ‘just because you are paranoid does not mean that no one is out to get you’. It is natural to consider whether something went wrong but this does not mean that they knew what had happened.

Although any claimant might have suspicions the concern is for those who suffer from a defect of mind, they are subject to these same (flawed) tests. They are unlikely to have the capacity to understand the nature and quality of the physician’s mistake even if it is explained to them. The lawyers may not be able to progress the case if their client cannot understand the mistake. It often falls to the claimant’s own GP (who might be the defendant) to explain the expert’s report. Often the claimant will discontinue the case if they feel they are not being listened to.

Conflicting instructions

Lawyers often struggle if they have a supportive medical report but the claimant rejects the conclusions. The lawyer can either follow the instructions from their claimant or the findings of the expert. This battle can continue past the conclusion of the case where the claimant then sues the lawyer for winning the case in the wrong way. There is no system to protect the lawyer from a claimant with a defect of mind who does not understand the nature and quality of the physician’s mistake.

The court of protection is uninterested in cases where the claimant generally has capacity but has problems with specific issues. Normal capacity assessments will not detect the problem and the courts will be loathe to interfere even in gross cases. The resultant letters of claim can be delusional and wholly unsupported by the evidence. Unsurprisingly this can lead to a break down in the lawyer – client relationship and the claimant then proceeds as a litigant in person. Unless the judge steps in to take control, these cases can clog up court time for years or even decades.

A disability analyst report (DAR) would assist in these cases by identifying what the claimant is unable to understand. A court ordered assessment would give a lawyer representing the claimant the power to write the letter of claim in their client’s best interests. It would allow the court to step in and amend the particulars of claim so that it was rational and consistent with medical evidence. DARs are low cost and many medical experts will already have made the relevant assessments as part of their standard examination.


Limitation should run from the moment that the person reasonably has knowledge of the nature and quality of the act. It should not be enough to know that something has happened, the person should also know that there was a mistake. In simple cases this can be presumed such as where a fracture was missed but in more complex cases expert advice may be required. In those with a defect of mind special protections should be in place such as a disability report looking for functional restrictions.

It should be standard practice for all lawyers to obtain a low-cost level 2 screening report whenever they are approach with a potential case. This would provide evidence that the claimant did or did not have a case and what their beliefs were at any specific time. Many claimants who later win their cases are turned away by lawyers with little or no explanation. An alternative would be a portal where unrepresented claimants could get an initial opinion directly and potentially remove the need for lawyers.

There should be a general duty on medical experts to draw the court’s attention to cases where a disability report is required. Where there is a disorder of mind that materially impedes the understanding the expert could write a brief note to the lawyers (or court). The legal team could then consider whether they are able to run the case despite their client’s disability. Allowing lawyers to apply for permission to write the letter of claim on best interests would be better than ceasing to act and leaving vulnerable claimants unrepresented.

Doctor Mark Burgin, BM BCh (oxon) MRCGP is on the General Practitioner Specialist Register.

Dr. Burgin can be contacted on This email address is being protected from spambots. You need JavaScript enabled to view it. and 0845 331 3304 website

This is part of a series of articles by Dr. Mark Burgin. The opinions expressed in this article are the author's own, not those of Law Brief Publishing Ltd, and are not necessarily commensurate with general legal or medico-legal expert consensus of opinion and/or literature. Any medical content is not exhaustive but at a level for the non-medical reader to understand.

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The opinions expressed in the articles are the authors' own, not those of Law Brief Publishing Ltd, and are not necessarily commensurate with general legal or medico-legal expert consensus of opinion and/or literature. Any medical content is not exhaustive but at a level for the non-medical reader to understand. 

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