Mazur v Charles Russell Speechlys [2025] EWHC 2341 (KB), which held only authorised persons can conduct litigation, has already prompted parties to challenge solicitors’ bills. 71% of costs lawyers attending the Association of Costs Lawyers (ACL) conference last week said they expect more Mazur-related challenges.
The costs lawyers reported judges are starting to check the qualifications of those appearing before them—43% of conference attendees polled said they expect this to become a regular occurrence post-Mazur.
ACL chair David Bailey-Vella said ‘record numbers’ of people have been applying to sit the costs lawyer professional qualification. ‘Costs is an unusual area of practice in that unqualified, unauthorised people have been doing much the same work as costs lawyers,’ he said.
Last week, the Solicitors Regulation Authority issued guidance on Mazur, warning it will take enforcement action against firms which do not address the implications of the case.




