Mazur and another v Charles Russell Speechlys LLP [2025] EWHC 2341 (KB) is a costs appeal that decides a much larger point. The Administrative Court held that employees of an authorised firm are not themselves entitled to conduct litigation merely because they are employed and supervised. This may sound mundane, but the consequences are profound. There are many, many firms of solicitors who allow grade D fee earners, or other unqualified staff to conduct litigation, in the time hallowed phrase “under the supervision of their principals”. This reflects the practice of the profession, going back to at least Victorian times, where the backbone of any litigation department, was the time served and unqualified managing clerk.
But this case suggests that the solicitors and unqualified staff, at any firm that is continuing that practice is breaking the law. And not only the regulatory law, but doubling down by committing criminal offences to boot. That is why this case matters. That is why it could be so damaging to the profession as a whole, and so surprising that it appears to have come out of left field, without much warning. The law is otherwise trite. Only authorised or exempt persons may “conduct litigation.” Section 21(3) of the Legal Services Act 2007 does not confer that entitlement. It defines who can be regulated. The judgment was handed down by Sheldon J on 16 September 2025.
Sheldon J discussed the statutory scheme. “Conduct of litigation” is a reserved activity . Entitlement is “solely” as the Legal Services Act 2007 provides, and exists only for an authorised or exempt person. It follows that this statutory scheme does not permit delegation: an authorised or or exempt person, cannot lend their authority to the work of unauthorised or non exempt persons, who are conducting litigation. Section 21 is about regulatory reach, not authorisation. It lets the SRA write and enforce “practice,” “conduct,” and “discipline” rules against both authorised persons and their employees. It does not convert employees into authorised persons. Reading it as a licence would contradict the architecture of sections 13–19.
The judge accepted the distinction advanced by the Law Society and the SRA. Unauthorised staff may support an authorised solicitor who takes responsibility for the case. They may not themselves conduct and control litigation, even if supervised. Where does this leave matters? First, high-volume practices that let non-admitted case-handlers sign, issue and engage the court may have to re-engineer their workflows. An authorised solicitor must own and execute the reserved steps.
Second, there will be satellite disputes about earlier pleadings issued or signed by the “wrong” person. The court in Mazur declined to strike out because the defects were now cured and strike-out would cause prejudice. But not every case will be so fortunate in timing or discretion. The risk is real. Indeed, one can see real tactical advantage to an opponent to litigation, if it is apparent from the pleadings, the precedent H, the correspondence that the litigation has been conducted by someone with no authority to conduct it.
Third, and inevitably, costs will be contested. If a firm relied on an unauthorised person to conduct litigation, the opponent may resist paying for those acts. They will point to the illegality of what has been done, and point to the requirements of public policy, in disallowing such costs. Instead of the retainer being illegal or unenforceable in its formation, the performance of the retainer will be said to be tainted by illegality. On the other hand, this decision has the potential to dramatically increase costs, if delegation cannot be lawfully done.
There are interesting reasons to question the correctness of the decision or to suggest that it may be “wrong”, but at High Court level, this judgment has detonated like a bomb over the profession. I predict, with a degree of confidence, that matters will not rest here. Once the tactical struggles break out, inevitably the correctness of this decision will be put in issue, and inevitably given that the author is a High Court judge, the matters will have to be ventilated in the Court of Appeal.