1928: May Donoghue worked as a shop assistant in Glasgow. She was 30 years old. On the evening of 26 August, she visited the Wellmeadow Café in nearby Paisley with a friend, who treated her to an ice-cream float. The café owner brought a tumbler of ice cream and a bottle of ginger beer, which he poured over the ice cream. (Important detail: the bottle was made of dark, opaque glass.) Donoghue consumed some of the float. When her friend refilled the tumbler, a decomposed snail slid out of the bottle. Donoghue felt unwell.
Assisted by Walter Leechman, a local solicitor, Donoghue sued the drinks manufacturer, David Stevenson, for breaching his duty of care, since he had failed to prevent the snail getting into the bottle – something that Donoghue had been unable to ascertain herself because the bottle was opaque.
Under existing law, Donoghue’s chances of success were slim, especially as she was not the actual purchaser of the drink. Donoghue, however, was a determined litigant, and Leechman was a determined solicitor.
The case went through the Scottish courts and eventually reached the House of Lords in London. On 26 May 1932 they ruled in favour of Donoghue. Lord Atkin declared that, because Donoghue couldn’t possibly have examined the contents of the bottle beforehand, Stevenson was obliged to ensure that his product was untainted. His lordship also enunciated a second, more far-reaching principle, based on the biblical story of the Good Samaritan – the “good neighbour” principle, whereby we all have a duty of care to our “neighbour”.
The House of Lords ruling represented a fundamental shift in the duty of care; the modern law of negligence owes much to the case of the so-called “Paisley snail” or “snail in the bottle”.
Source: Donoghue v. Stevenson and the Modern Law of Negligence: The Paisley Papers: The Proceedings of the Paisley Conference on the Law of Negligence, ed. Peter T. Burns, QC, and Susan J. Lyons (1991), pp. 1–24