"Public opinion, nowadays, is the opinion of the bald-headed man at the back of the omnibus. It is NOT the opinion of the aristocratical classes as such; or of the most educated or refined classes as such; it is simply the opinion of the ordinary mass of educated, but still commonplace mankind."
When Walter Bagehot included this line in his famous treatise The English Constitution published in 1867, little did he know that it shall lead to the creation of a of a legal phrase denoting the standard of reasonable care, which shall last more than a hundred years.
It was in 1903 that the “man on the Clapham omnibus” made his debut in judicial decisions when his mention appeared at page 109 in the judgement, McQuire v Western Morning News Company Limited. ‘The man on the omnibus’ became ‘the man on the Clapham Omnibus’ with a typical working class London neighbourhood selected as his destination lest anyone mistake him to be from the upper class elite.
However, his moment of glory definitely came in the 1933 case of Hall v. Brooklands Auto Racing when Greer L.J. of the Court of Appeal held "…the man in the Clapham omnibus taking a ticket to see a cricket match at Lord's would know quite well that he was not going to be encased in a steel frame which would protect him from the one in a million chance of a cricket ball dropping on his head. …In my opinion, in the same way such a man taking a ticket to see motor races would know quite well that no barrier would be provided which would be sufficient to protect him in the possible but highly improbable event of a car charging the barrier and getting through to the spectators. The risk of such an event would be so remote that he would quite understand that no provision would be made to prevent it happening, and that he would take the risk of any such accident.” Poor, Mr. Hall who had obtained damages of 998 shillings from the lower court had the judgement in his favour set aside due to the implied terms in the contract for purchase of the ticket which ‘the man on the Clapham omnibus’ would have known. More than 110 years after its first use, the ‘Man on the Clapham Omnibus’ is still often invoked by the judges across common law jurisdictions.
However, what is uncommon is judges accepting the test for what it really is – judges dictating what ought to be. When the reasonable man test or any tests of like nature are applied, the court judges the situation not by considering what the persons involved in the case thought or not by taking evidence as to what the average view in the country is but by actually subjectively making a decision on the basis of what the judges think the reasonable man’s perspective is or ought to be. Thus the persons on the Clapham omnibus are actually none other than the judges themselves!
Recently, the United Kingdom Supreme Court speaking through Reed L.J. in Healthcare at Home Ltd. v. Common Services Agency has elaborated eloquently about the various new legal fictions similar to the man on the Clapham Omnibus that the courts have come up with in recent times. I am reproducing the first four paragraphs from that wonderful judgement here -
1. The Clapham omnibus has many passengers. The most venerable is the reasonable man, who was born during the reign of Victoria but remains in vigorous health. Amongst the other passengers are the right-thinking member of society, familiar from the law of defamation, the officious bystander, the reasonable parent, the reasonable landlord, and the fair-minded and informed observer, all of whom have had season tickets for many years.
2. The horse-drawn bus between Knightsbridge and Clapham, which Lord Bowen is thought to have had in mind, was real enough. But its most famous passenger, and the others I have mentioned, are legal fictions. They belong to an intellectual tradition of defining a legal standard by reference to a hypothetical person, which stretches back to the creation by Roman jurists of the figure of the bonus paterfamilias. As Lord Radcliffe observed in Davis Contractors Ltd v Fareham Urban District Council
“The spokesman of the fair and reasonable man, who represents after all no more than the anthropomorphic conception of justice, is and must be the court itself.”
3. It follows from the nature of the reasonable man, as a means of describing a standard applied by the court, that it would misconceived for a party to seek to lead evidence from actual passengers on the Clapham omnibus as to how they would have acted in a given situation or what they would have foreseen, in order to establish how the reasonable man would have acted or what he would have foreseen. Even if the party offered to prove that his witnesses were reasonable men, the evidence would be beside the point. The behaviour of the reasonable man is not established by the evidence of witnesses, but by the application of a legal standard by the court. The court may require to be informed by evidence of circumstances which bear on its application of the standard of the reasonable man in any particular case; but it is then for the court to determine the outcome, in those circumstances, of applying that impersonal standard.
4.In recent times, some additional passengers from the European Union have boarded the Clapham omnibus. This appeal is concerned with one of them: the reasonably well-informed and normally diligent tenderer
  2 KB 100
  1 KB 205
 I do wonder if he had been ruling in the present era, Greer L.J. would indulge in this cricket analogy, seeing how often the likes of Gayle dispatch the ball into the crowd.
 This is so weird. Since I never have had to cite a post-2009 UK Apex Court case in any of my writings till date, this is the first time I am citing the UK Supreme Court as opposed to the House of Lords. I know and appreciate the arguments regarding strict separation of power but it still feels weird to cite the UKSC.
 He shall be one of the last few Lord Justices (L.J.). New UKSC judges appointed herewith shall not be elevated to the House of Lords.
  UKSC 49
  AC 696, 728: