Marking an end to the last six months of uncertainty and disruption amongst the legal profession, the Court of Appeal has now delivered a landmark judgment clarifying what it means to ‘carry on the conduct of litigation’ under the Legal Services Act 2007 (‘LSA’). Their decision in Mazur & Anor v Charles Russell Speechlys LLP [2026] EWHC Civ 369 (‘Mazur’) has restored the long‑established principle that unauthorised staff may perform litigation tasks under appropriate supervision, without committing a criminal offence. This article explores the decision in Mazur, with a particular focus on what the decision means, in practical terms, for law firms and legal service providers.
The High Court’s Approach
As discussed in our first article in this series: Trainees and the Conduct of Litigation: clarifying the limits after Mazur v Charles Russell Speechlys [2025] by Amy Williams, Paige Layzell-Payne and Sophie Korine | Sinclair Gibson, the High Court ruled that unauthorised individuals could ‘support or assist’ an authorised solicitor but could not perform acts amounting to the conduct of litigation itself. This decision created a “real world impact”, as described by the Legal Services Board (an intervener in the appeal), with tensions arising between the business models of legal service providers and the decision in the High Court. In particular, the High Court’s reasoning caused ambiguity as to the legitimacy of routine delegation practices (widely adopted by law firms and other legal service providers), and whether these delegation practices could be continued without risking criminal liability.
The Court of Appeal’s Clarification
The Court of Appeal, led by Sir Colin Birss, rejected the High Court’s distinction between ‘supporting and assisting’ and ‘conducting litigation’, and concluded that ‘unauthorised persons’ could perform tasks that constitute the conduct of litigation, as long as an authorised person retains responsibility. Sir Colin Birss provided a helpful summary of the position at [25] of the judgement:
“An unauthorised person can lawfully perform any tasks … within the scope of the conduct of litigation, for and on behalf of an authorised individual … The authorised individual retains responsibility for the tasks… The authorised individual is, therefore, the person carrying on the conduct of litigation. … The unauthorised person is not carrying on the conduct of litigation and does not commit an offence.”
The Court of Appeal’s line of reasoning was that the distinction between the two phrases (‘supporting and assisting’ and ‘conducting litigation’) could largely be traced back to two particular case law authorities Ndole Assets v Designer M & E Services [2018] EWCA Civ 2865 (‘Ndole’), and Baxter v Doble [2023] EWHC 486 (KB) (‘Baxter’). However, the Court of Appeal found that both these cases were fundamentally different from Mazur.
In both Ndole and Baxter, there were no authorised persons conducting litigation at all (there was an unauthorised person assisting a litigant in person, with no authorised person responsible for the conduct of the litigation), whereas Mazur involved an authorised person delegating work to a supervised individual. At [27], Sir Colin Birss stated:
“…the conduct of litigation is not limited merely to assisting or supporting an authorised individual, and the distinction drawn in the court below by the Law Society and SRA, and adopted by the judge, between (a) supporting (or assisting) and (b) conducting litigation under supervision was not correct.”
Instead, the Court of Appeal analysed the issue through the lens of who is legally responsible for the litigation. In his conclusion, Sir Colin Birss at [187] stated:
“An unauthorised person may lawfully perform any tasks which are within the scope of the conduct of litigation, for and on behalf of an authorised individual, such as a solicitor or an appropriately authorised CILEX member, provided the authorised individual retains responsibility for the tasks delegated to the unauthorised person…”.
Therefore, it is clear that an ‘unauthorised person’ may perform tasks falling within the conduct of litigation, provided they do so on behalf of and under the responsibility of an authorised person. Nonetheless, the court did highlight the paramount importance of effective supervision in these cases.
The Scope of the ‘Conduct of Litigation’
The Court of Appeal did not provide a comprehensive list of activities falling within or outside the definition of conducting litigation. In fact, at [29], Sir Colin Birss stated that doing so would be “simply not possible”.
However, the court did indicate some tasks which are unlikely, in themselves, to amount to the conduct of litigation:
Ultimately, the difficulty in producing an exhaustive list underlines that the analysis in every situation is contextual and highly dependant on the facts of the specific scenario. Further information can be found in the Law Society’s guidance note, published on 13 April 2026, which advises on how solicitors, law firms, and legal businesses can ensure that only those authorised to do so carry on the conduct of litigation: Mazur and the conduct of litigation | The Law Society.
Practical Implications
The Court of Appeal’s decision in Mazur has immediate and practical consequences for those operating in the legal industry and under the LSA. For many, it will be reassuring that tasks falling within the conduct of litigation may be delegated to unauthorised persons, such as trainees, thereby preserving the team-based delivery model commonly used in practice. However, it has been made clear that this is subject to legal responsibility remaining with the authorised person and the effective supervision.
Law firms and other businesses operating in the legal industry should review their delegation structures and processes to ensure that they are clearly defined, with active oversight of trainees, paralegals, and other support staff. As the Court of Appeal noted, supervision and control are ultimately a matter for the regulators, and firms should be alert to further guidance from bodies such as the Solicitors Regulation Authority and the Law Society. Firms may also wish to implement a culture of ongoing review and enhancement of their supervisory processes to ensure adherence to the LSA and relevant regulatory guidance.
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