Duty of Good Faith in UK Law

A fiduciary is someone who has undertaken to act for or on behalf of another in a particular matter in circumstances which give rise to a relationship of trust and confidence. A fiduciary must act in good faith; he must not make a profit out of his trust; he must not place himself in a position where his duty and his interest may conflict; he may not act for his own benefit or the benefit of a third person without the informed consent of his principal.

Even if a fiduciary is properly acting for two principals with potentially conflicting interests he must act in good faith in the interests of each and must not act with the intention of furthering the interests of one principal to the prejudice of those of the other: see Finn (op.cit.) He must not allow the performance of his obligations to one principal to be influenced by his relationship with the other. He must serve each as faithfully and loyally as if he were his only principal.

It is plain from these authorities that a decision-maker's discretion will be limited, as a matter of necessary implication, by concepts of honesty, good faith, and genuineness, and the need for the absence of arbitrariness, capriciousness, perversity and irrationality.

The second is that, as seen from the Carewatch Care Services case, an implication of a duty of good faith will only be possible where the language of the contract, viewed against its context, permits it. It is thus not a reflection of a special rule of interpretation for this category of contract.

Such "relational" contracts, as they are sometimes called, may require a high degree of communication, cooperation and predictable performance based on mutual trust and confidence and involve expectations of loyalty which are not legislated for in the express terms of the contract but are implicit in the parties' understanding and necessary to give business efficacy to the arrangements.

No single one of the above list is determinative, with the exception of the first one. This is because if the express terms prevent the implication of a duty of good faith, then that will be the end of the matter. However, many of these characteristics will be found to be present where a contract is a relational one. In other cases on entirely different facts, it may be that there are other features which I have not identified above which are relevant to those cases.

They are duties in equity imposed in order to ensure that a receiver, while discharging his duties to manage the property with a view to repayment of the secured debt, nonetheless in doing so takes account of the interests of the mortgagor and others interested in the mortgaged property. What a mortgagee or a receiver must do to discharge them depends upon the particular facts of the particular case.