Fiduciary relationships arise in equity’s exclusive jurisdiction and are relationships to which equity grants particular protection. Fiduciary obligations are owed by the fiduciary to identified others or a group of people, often described as the principal of the obligation or, somewhat confusingly, the beneficiary to whom the obligation is owed. In broad terms, the core obligation of a fiduciary is undivided loyalty. The fiduciary must act exclusively in the interests of the beneficiary. This obligation is not unbounded; for example, fiduciary obligations may be limited by time or the nature of the activities giving rise to the obligation in question. Fiduciary obligations thus exist within a defined scope. Additionally, not all of the obligations owed by the fiduciary to the beneficiary will be fiduciary obligations. For example, a trustee may be required to exercise a degree of care when making investment decisions, but this obligation is not fiduciary in nature.

Equity closely scrutinises relationships in which one party places trust and confidence in another. There are many examples of trust in human interaction, but equity cannot grant relief against every breach of trust and confidence, any more than contract law can enforce all promises. Only some trusting relationships and some obligations of confidence are protected. The relationships which equity protects are known as ‘fiduciary relationships’. A relationship of trust and confidence will be recognised as fiduciary where it arises from F (fiduciary) undertaking to act in the interests of B (beneficiary) in a matter which confers a discretion on F, and in respect of which the exercise of discretion affects B’s economic interests. B may hand over property to F, such as an investor handing over money to an investment adviser. A settlor may hand property to F to hold on trust for B. Alternatively, B may entrust F with the task of negotiating a contract on behalf of B so that F is B’s agent. Or F may be entrusted with the task of obtaining information on behalf of B which will enable B to exploit a commercial opportunity. This is also an example of agency.

Trust matters to fiduciary law in a variety of ways. This chapter will focus on the importance of trust in advisory relationships, and it will emphasize two settings: categorical fiduciary relationships and ad hoc fiduciary relationships. In the former setting, I will suggest that these relationships are appropriately treated as fiduciary in part due to the likelihood of a beneficiary’s epistemic dependence on a fiduciary’s judgements. It is not necessary for epistemic dependence to exist in any particular advisory relationship to support this categorical treatment, so long as the likelihood of epistemic dependence is high enough across the category. In turn, the presence of trust supports the likelihood of that epistemic dependence. In the ad hoc fiduciary setting, I will suggest that these relationships are sometimes best seen as a kind of “involvement” (as that concept is developed in David Owens’s work). Involvements are voluntary relationships even though they may have no precise moment when they come into existence. Importantly, the existence of involvements is generally recognizable by the parties involved. Trust is relevant here as an aid in legally identifying such relationships.

Political (Dis)Trust and Fiduciary Government analyzes the relationship between two key ideas in modern political thought: political trust and fiduciary government. The chapter begins with fiduciary government. Miller distinguishes ‘thick’ from ‘thin’ variants on the idea of fiduciary government. Thick variants place substantial normative weight on the idea, claiming, for example, that it solves the problem of political authority and provides an independent normative basis for the recognition of specific legal rights. Thin variants make much more modest claims. Miller’s own thin account, deployed here, suggests that fiduciary government articulates conditions under which the conduct of government can be understood as truly representative. By comparison with this thin conception of fiduciary government, an understanding of political trust as a particularized (or focused) and objective (or manifest) form of trust shown (or withheld) by citizens in public officials does distinct work. Briefly: it illuminates understanding of the political conditions and activity on which fiduciary government depends. That said, Miller also notes that ideals of fiduciary government and of political trust, where instantiated, dovetail: demands of fiduciary government enable public officials to prove trustworthy in ways that promote political trust, while also creating space for constructive forms of political distrust.