The purpose of this article is to examine when a right to set off independent cross demands may be available in a case in which an agent acting on behalf of a principal has contracted with a third party. Three particular situations are considered. The first involves the series of cases dealing with undisclosed principals, in which the third party was not aware at the time of the contract that the person with whom he was dealing was merely acting as an agent on behalf of another. The principal subsequently sues the third party on the contract, and the question is whether the third party may bring into account a debt owing to him by the agent on a separate and independent transaction. The second situation arises when the agent, rather than the principal, is the person in whose name the action against the third party is being prosecuted. The third party may wish to set off in that action a debt owing to him by either the principal or the agent on another transaction. Finally, the question of a right to set off independent cross demands may arise in an action brought by the third party against the agent.

The position of applicants for judicial review has been drastically ameliorated by the new Order 53. It has removed all those disadvantages, particularly in relation to discovery, that were manifestly unfair to them and had, in many cases, made applications for prerogative orders an inadequate remedy if justice was to be done … Now that those disadvantages to applicants have been removed and all remedies for infringements of rights protected by public law can be obtained upon an application for judicial review, as can also remedies for infringements of rights under private law if such infringements should also be involved, it would in my view as a general rule be contrary to public policy, and as such an abuse of the process of the court, to permit a person seeking to establish that a decision of a public authority infringed rights to which he was entitled to protection under public law to proceed by way of an ordinary action and by this means to evade the provisions of Order 53 for the protection of such authorities.

(per Lord Diplock in O'Reilly v. Mackman [1983] 2 A.C. 237 at 285)

If Jurisprudence strikes the law student as a miry bog, the analysis of a legal right ought, at least, to provide a path through the marshland. The disparate rumours of such a path may have a greater tendency to lead him into the middle of the bog than bring him safely to the other side.

The prevalent view of English lawyers as stated by Megarry & Wade1 is that “it is most unlikely that a right would be accepted as an easement if it involved the servient tenant in the expenditure of money; for none of the recognised easements does so, except the obligation to fence in order to keep out cattle.” This view has been expressed as a rule of law in the recent case of Ranee v. Elvin.2 Whether as a rule or as a mere presumption, it is widely regarded as part of the very fabric of the law of easements: timeless and immutable.