Clinical Negligence Ep 2: The Snail and the Bottle Case

Doctors play a crucial role in society, forming the backbone of most medical systems worldwide by directly administering essential medical care. This reliance places a heavy responsibility on doctors, one with severe consequences for the patient if medical practitioners are derelict in their duties. In this article series, we explore the definitions and origins of negligence, and analyse how negligence occurs in the medical context.

Previously, we highlighted the tragedy of the Shewrys, where ill-advised injections to Leslie Shewry administered by Dr Lysander Maybury ultimately led to the former’s death and no significant consequences for the latter, and the inadequacies of the law in guarding against medical malpractice. In this issue, we shall focus our attention on a landmark case that would revolutionise the practice of tort law, which is the arm of the law that handles civil wrongs and includes the handling of medical negligence.

The makings of this transformative case started with an innocuous trip to a cafe in Paisley, Scotland. There, a friend treated Mrs May Donoghue to a ginger beer ice cream float. The cafe owner poured some ginger beer out of an opaque glass bottle labelled “Stevenson and Co.” into a tumbler with the ice cream before serving the bottle and tumbler to the pair. As her friend poured the remainder of the ginger beer into the tumbler, the decomposed remains of a snail floated out from the bottle into the tumbler. This sighting gave her a great fright, and she felt abdominal pain immediately after. Within a week, she had to see a doctor, and less than a month later, she was sent to the Royal Glasgow Infirmary (Hospital) for “emergency treatment” for severe gastroenteritis and acute stress reaction. Following which, she issued proceedings against Mr David Stevenson, the presumed manufacturer of the contaminated ginger beer, in a case that would become known as Donoghue v Stevenson [1932].

In her case, Mrs Donoghue argued that Mr Stevenson owed a duty of care to his customers who consumed his products to make sure that they were clean and would not harm his customers, regardless of the presence of a contract. On the other hand, Mr Stevenson argued that certain facts of the case were not proven, the claim for damages was excessive, and Mrs Donoghue’s medical issues were not caused by him but rather by her own ill health.

At this juncture, it is worth pausing to think of what Mrs Donoghue likely felt when faced with a decomposed snail in the bottle of ginger beer she had drunk from, obvious as it may seem. Firstly, this unexpected and horrifying discovery would have triggered a sudden onset of anxiety. This anxiety causes the release of stress hormones in the brain, including adrenaline and cortisol, which in turn trigger electrical signals. These signals are then transmitted via the vagus nerve to the enteric nervous system, which controls the gastrointestinal tract. This direct connection between the central and enteric nervous system results in the gut being highly sensitive to changes faced by the brain, including this sudden onset of stress. With elevated cortisol and adrenaline levels, the gut muscles would tense up, reducing gut motility and resulting in discomfort eventually. In addition, the pain threshold may be lowered, resulting in normal physiological processes being perceived as painful. Finally, inflammation of the stomach may occur, which triggers the slightly painful condition functional dyspepsia, simply known as indigestion. In short, Mrs Donoghue would likely have experienced immediate abdominal pain upon the snail sighting, which she duly did.

In addition, a decomposing snail has certain implications for the ginger beer that Mrs Donoghue consumed in part. Decomposition is a process whereby microorganisms like fungi and bacteria break down complex organisms into simpler substances, including carbon dioxide. Outside a beer bottle, this process is simply an essential part of the carbon cycle, helping to recycle carbon material from dead organisms to be taken up by plants as carbon dioxide during photosynthesis. Inside, however, the very presence of decomposition indicates a large amount of microorganisms that could be floating in the beer bottle, some of which could be pathogenic. Not to mention the fact that snails, as soil-dwelling organisms, would likely have their own microbiota of potentially harmful organisms. These two facts, when combined, provide the requisite ingredients for a case of severe food poisoning.

Finally, with this sudden stressful event, it was also likely that Mrs Donoghue would experience an acute stress reaction. This is especially in light of the severity of the abdominal pain she faced after ingesting the snail-contaminated ginger beer.

With this biological basis, it is evident that a reasonable person, regardless of prior health condition, would likely develop the medical conditions faced by Mrs Donoghue upon sighting the decomposing snail. Hence, Mr Stevenson’s contention that Mrs Donoghue’s medical conditions were caused by her poor health rather than the snail in the bottle held little water, if any.

The contention that “Mrs Donoghue’s medical conditions were not caused by [Mr Stevenson]” was decidedly more complex. While the snail in the bottle is rightfully attributed as the cause of Mrs Donoghue’s medical conditions, whether Mr Stevenson had any legal responsibility for the snail being in the ginger beer bottle (i.e. duty of care) was up for question.

Firstly, there was a conspicuous lack of a contract between Mrs Donoghue and, well, anyone. As the ginger beer ice cream float was purchased as a “gift” by her friend from the cafe owner, Mrs Donoghue was not a party in any contract between the owner who supplied the beer to her, or Mr Stevenson who presumably manufactured the beer. Hence, she was unable to claim a breach of warranty for the ginger beer as Mr Stevenson technically had no contractual obligation to ensure the safety of the beer to Mrs Donoghue.

This situation did not bode well for Mrs Donoghue. In a previous case, Mullen v AG Barr & Co Ltd [1929], a decomposing rat was found in a bottle of ginger beer. This resulted in the 2 children who later consumed the beer to suffer from food poisoning. In this case, the lack of a contract and hence contractual obligation resulted in the Court of Session, the second highest level of courts in the United Kingdom, ruling in favour of AG Barr & Co. This was also known as the Privity of Contract, a common law principle that established the fact that only parties in a contract can acquire rights or have obligations imposed on them. Both Mr Mullen’s and Mrs Donoghue’s cases made two exceptions for if the manufacturer knew that the product was dangerous or the product was inherently dangerous. Mr Stevenson’s lawyers argued that none of these stipulations applied to Mr Stevenson as he was unaware of the snail in the ginger beer bottle, and ginger beer was not intrinsically dangerous. Mrs Donoghue’s case, if successful, would directly contravene legal precedent and violate this principle.

There was a bit of hope initially, with the initial judgement from the Court of Sessions favouring Mrs Donoghue, with the presiding judge determining that the principle was scoped too narrowly. However, Mr Stevenson appealed this decision, and the Court of Sessions allowed the appeal proceed by citing Mullen as precedent. At this point, Mrs Donoghue could have just given up, like Mr Mullen in his case. However, she decided to use one last legal avenue to secure a victory: an appeal to the House of Lords.

While we could have spent time breaking down the debate between the 5 Lords that presided over this judgement, we will instead focus on the decidedly more interesting topic of the two opinions presented by the Lords. The dissenting opinion was largely similar to what was discussed above. In comparison, the majority opinion, as delivered by Lord Atkin, would have profound consequences to tort law and introduce the doctrine of negligence today.

In his majority opinion, Lord Atkin established that there was a duty of care from Mr Stevenson to Mrs Donoghue to ensure that his products did not inadvertently harm her. In doing so, he established negligence as a distinct and separate tort, or civil wrong. This severed the dependence of a case of negligence on a contract, meaning that negligence cases could be pursued outside of contractual terms. In addition, he also maintained that a duty need not be based on a contractual relationship, and stated that manufacturers owe a duty of care to the consumers of their products. This meant that the Privity of Contract was not a valid legal defence for Mr Stevenson.

The most famous implication of Lord Atkin’s judgement, however, remains the Neighbour Principle. As the famous excerpt from his statement reads:

“You must take reasonable care to avoid acts or omissions which you can reasonably foresee would be likely to injure your neighbour. Who, then, in law, is my neighbour? The answer seems to be persons who are so closely and directly affected by my act that I ought reasonably to have them (in consideration).”

Simply put, everyone, regardless of professional occupation or status, has an inherent duty of care to their neighbours by ensuring one’s actions do not intentionally or inadvertently injure or harm them. He proceeds to define neighbours as people who one would reasonably foresee to be affected by his action or non-action such that he would have to account for their interest in making decisions. This neighbour principle applied to Mr Stevenson in that he had a duty of care to the consumer of his ginger beer, in this case Mrs Donoghue, as he could reasonably foresee someone consuming his ginger beer.

This principle was not unanimously agreed upon, as represented by a 3-2 split in the House of Lords. However, Donoghue vs Stevenson would set a landmark precedent in the pursuit of negligence cases, and contributed to a rise, whether for better or for worse, in personal injury claims against companies for negligence.

However, its most significant impact would be in medical negligence cases. Lord Atkin had the foresight to realise the judgement would have a significant impact on public health matters. As medical practitioners were effectively providers of treatment to their patients, they owed a duty of care to prevent injury or harm to their patient, regardless of the presence of contractual obligation. If their actions or non-actions led to patient harm, similar to Mr Stevenson manufacturing the ill-fated bottle of ginger beer, they would be legally responsible for medical negligence to the patient. Without oversimplifying matters, the Neighbour Principle enabled cases of medical negligence, like that of the Shewrys previously, to be given a fighting chance in court instead of being shut out by the machinations of practitioners with questionable objectives.

With this groundbreaking historical precedent established, future issues will examine modern cases of clinical negligence in both local and foreign contexts. These cases vary in location, verdict and type of clinical negligence, but the reason why all were brought to court was in part due to a perceived lack of consideration of the patient in the doctor’s action or inaction.

Before we end today’s issue, we shall return to the first claim that Mr Stevenson’s lawyers made; that “the facts of the case were not proven”. In fact, they remain unproven to this day. Up till now, no one knows if there was an actual snail in the ginger beer bottle, or if the beer, beer bottle (and snail) was actually manufactured by Mr Stevenson’s company. At that time, beer bottles were often reused, and these bottles sometimes were sent to a different beer manufacturer. It was plausible that Mr Stevenson’s company simply refilled the bottle without knowing that a decomposing snail was in the bottle, labelled it and sent it on its way. It was also possible that another company refilled the bottle labelled with Mr Stevenson’s company and accidentally introduced the decomposing snail into it. We still do not know, and will likely never know, whether the snail came from Mr Stevenson’s company, another company, or if it even existed at all. That being said, even if Mrs Donoghue’s case was entirely fabricated, it ultimately led to the establishment of negligence as its own tort, which would dramatically impact the way negligence cases, including those that involved medical negligence, were judged in court. Ultimately, what matters in the long term is the case’s verdict and its impact on society.

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Image Credit: https://hearsay.org.au/carbon/assets/2022/05/Snail-scaled-e1653545507424.jpg