The Role of Fiduciary Duties in UK Legal Practices

Why fiduciary duty matters

Fiduciary duty is one of the law's answers to dependency. A person entrusts another with power, information, discretion or property. The law then asks whether that power has been exercised for the proper purpose, in the interests protected by the relationship, and without unauthorised conflict or gain.

That is why fiduciary duty remains central to public confidence in legal services. Clients do not usually see the full internal machinery of a file. They do not know every conflict check, every interest disclosed by a referrer, every handling step for client money, every information barrier or every private conversation inside a firm. They rely on professional loyalty and on systems that make loyalty more than a slogan.

The fiduciary idea is therefore practical. It helps explain why a solicitor cannot treat a client file as a commercial opportunity, why confidential information cannot be used for another purpose, why informed consent matters, and why conflicts must be identified before they damage the client's position. The language is old, but the problem is current: trust without accountability is not enough.

The historical roots

Modern fiduciary law draws heavily from equity and trust law. The older cases are not merely historical decoration. They explain why the law treats conflicts and unauthorised profits strictly, even where the fiduciary says they acted honestly or achieved a useful result.

Keech v Sandford is commonly cited as an early expression of the strict no-conflict principle. A trustee could not take for himself an opportunity connected with the trust property, even where the opportunity was said not to be available to the beneficiary. The rule protected the beneficiary by removing the temptation and the evidential difficulty of asking whether the fiduciary's conduct was actually harmful.

Boardman v Phipps later illustrated the severity and nuance of the principle. A solicitor and a beneficiary made a profit after using information and opportunity connected with a trust. The trust benefited, but the fiduciary issue remained. The case is often used to show that fiduciary liability is not simply about fraud, bad faith or loss. It is about unauthorised conflict and unauthorised profit in a relationship of trust.

Lehtimäki v Cooper is a modern Supreme Court example from a different context: charitable company governance. It confirms that fiduciary analysis continues to matter in complex structures, including where company law, charity law and trust principles meet. The modern law does not abolish fiduciary discipline; it adapts the discipline to the relationship in question.

Definition and scope

A fiduciary relationship arises where one person has undertaken to act for or on behalf of another in circumstances that give rise to duties of loyalty. The label does not attach to every relationship of trust, and it does not convert every contractual failure into a fiduciary breach. The relationship, the undertaking and the function being performed all matter.

Common examples include trustees and beneficiaries, solicitors and clients, directors and companies, agents and principals, partners, and some professional advisers when they assume responsibilities involving loyalty and discretion. The content of the duty depends on the context. A trustee, solicitor, director and agent may all be fiduciaries, but the precise duties and remedies are not identical in every setting.

The central duties usually include avoiding conflicts of interest, not making unauthorised profits, not misusing confidential information or opportunities, and acting for the proper purpose within the entrusted role. In legal practice, those fiduciary duties interact with professional rules, client-care obligations, the law of confidentiality, privilege, costs duties, client-money rules and complaint systems.

Application in legal practice

For solicitors, fiduciary duty is not isolated from regulation. The SRA Principles require solicitors to uphold the rule of law and the proper administration of justice, uphold public trust and confidence, act with independence, honesty and integrity, and act in each client's best interests. Those principles are not a complete statement of fiduciary law, but they reflect the same basic demand for loyalty and trustworthiness in professional work.

The practical settings are familiar. A solicitor may hold confidential information from a former client. A firm may be asked to act for two clients whose interests appear aligned but may later diverge. A referral arrangement may create a financial interest that must be disclosed. A client-account issue may raise questions about safeguarding money. A settlement recommendation may require scrutiny if the solicitor's interests, workload, fees or third-party relationships have influenced the advice.

None of those situations proves a breach by itself. The proper question is what the solicitor knew, what role they had assumed, what interest or conflict existed, what was disclosed, whether informed consent was obtained, and whether the firm kept an audit trail capable of justifying the decision. Evidence turns a concern into an accountable issue.

Conflict, profit and consent

Conflict is the core fiduciary problem. The law is concerned not only with actual betrayal but with the danger that a fiduciary's judgment may be affected by another interest. That is why fiduciary duties often operate strictly. The question is not always whether the fiduciary acted with bad faith. The question may be whether the fiduciary placed themselves in a position where duty and interest, or duty and duty, conflicted without proper authority.

Informed consent is therefore essential. Consent is not a box-ticking exercise. It must be meaningful, based on sufficient information, given by the right person and recorded clearly. A client cannot sensibly consent to a conflict they do not understand, and a firm cannot rely on vague awareness where the material consequences were not explained.

Professional regulation adds a working structure. The SRA Code restricts acting where there is an own-interest conflict, a significant risk of one, a client conflict, or a later matter adverse to a former client where material confidential information is held, unless the relevant conditions are met. That regulatory framework does not replace fiduciary law, but it gives practitioners practical checkpoints.

Consequences and remedies

The consequences of fiduciary breach can be serious. Depending on the facts, the response may include an account of profits, equitable compensation, rescission, injunctions, delivery up of information, removal from a role, professional disciplinary action, or a complaint route through the firm, the Legal Ombudsman or the SRA.

The remedy depends on the wrong. A loss-based negligence claim asks different questions from an account of profits. A client-money issue may engage the SRA Accounts Rules and safeguarding obligations. A conflict issue may require analysis of consent, information barriers and whether the firm should have acted at all. A confidentiality issue may focus on whether information was misused, disclosed or deployed in a later adverse matter.

For clients and litigants in person, the practical step is to avoid using fiduciary duty as a catch-all phrase. A stronger complaint identifies the duty, the role, the conflict or profit, the information used, the decision affected, the documents proving it and the remedy being sought. Precision makes the issue harder to dismiss.

Modern challenges

Fiduciary duties now operate in a legal market shaped by complex firm structures, referral networks, alternative business structures, litigation funding, technology platforms, outsourcing, artificial intelligence tools and high-volume claims models. Those developments do not remove fiduciary obligations. They make the evidence trail more important.

Technology creates particular pressure points. A firm using automated triage, document review, client portals or AI-assisted drafting must still control confidentiality, competence, supervision and conflicts. If client information moves through systems or third-party providers, the fiduciary concern becomes practical: who has access, for what purpose, under what safeguards, and with what record?

Future disputes are likely to focus less on the label fiduciary and more on proof. Was the client told about the relevant interest? Was the conflict search adequate? Did the firm use confidential information for a later purpose? Was client money protected? Was the recommendation independent? Did the system design preserve loyalty, or did it quietly prioritise volume, referral income or commercial convenience?