One of the most disturbing features of the law of tort in recent years is the way in which the courts have extended, seemingly without any reference to considerations of policy, the liability for independent contractors. An independent contractor may be defined for the present purpose as any person, other than a servant, who is employed to do work. The definition includes such diverse persons as a builder, a road construction engineer, an electrician, a dentist or doctor attending a private patient, a shoe-repairer, a launderer, a dressmaker, a barber, an airline company, a taxi-driver, a copy-typist, an advisory expert, and a charwoman if not a servant. But a vendor is clearly not a contractor for this purpose (so that if, for example, I order a particular type of gunpowder to be made for me as a purchaser, I am not to be regarded as an employer of an independent contractor, and will not be liable, if the seller's works blow up, under any of the heads of liability to be discussed presently). Similarly it is submitted that a landlord who covenants to repair is not an independent contractor for the tenant; hence such rules of liability for contractors as have been developed would not apply to the tenant. The landlord would be an independent contractor for the law of tort only if it were contemplated that he was to do the repairs himself or by his servants.

Sir Frederick Pollock once said that the phrase res gesta meant in English neither more nor less than part of the story. This indicates that the idea behind this principle of the law of evidence is fundamentally a simple one, yet the present state of the law is such that a learned judge may confess without shame that he sees as through a glass darkly, and of the writers, Wigmore and Julius Stone, despairing of finding any firm basis for any such principle, favour a fresh start upon a different foundation or foundations. The general impression conveyed to lawyers is of an idea of great amplitude, and one fraught with tremendous possibilities. Lord Blackburn, a Victorian common lawyer, and Harman J., a modern Chancery judge, both jocularly advise any counsel seeking to obtain admission of a doubtful piece of evidence to pin his faith in res gesta. The feeling that at a pinch the doctrine might give some relief is not unjustified. Owing to the many exclusionary rules of the law of evidence, it is rarely possible to tell a plain tale in court. The importance of the res gesta principle is that where it applies it will nullify certain of these exclusionary rules. An act, a declaration accompanying an act, or a mere declaration may form part of the res gesta. Before qualifying for admission, all such evidence must satisfy the test of relevancy in the sense of materiality. In the case of an act, this is normally the only test, at any rate if the act is offered in evidence for its own sake, and not as equivalent to an assertion of fact or opinion.