Lawyers representing more than a million British motorists in the UK’s largest-ever diesel emissions claim have been accused of “over-lawyering” and racking up excessive fees totalling more than £76 million.
The class action, brought against a number of major vehicle manufacturers including Mercedes-Benz, Ford, Nissan, Renault, and Peugeot-Citroën, alleges the use of illegal “defeat devices” to cheat emissions tests, resulting in vehicles emitting more pollutants than advertised.
Leading the case for the claimants are London law firms Pogust Goodhead and Leigh Day, who represent the majority of the 1.5 million claimants. They argue that affected diesel vehicles were mis-sold to consumers and seek compensation on behalf of drivers.
But at a pre-trial costs hearing in the High Court this week, lawyers for the car manufacturers challenged the scale of the legal fees being forecast by the claimants’ side, describing them as “eye-watering”.
They told the court that the combined costs budget put forward by the claimant firms totalled £76.25 million, including £3.42 million already spent and a further £72.83 million in proposed spending.
Defence lawyers questioned the proportionality of the figure, especially given that two experienced lead law firms were managing the claim and that the case involves substantial commonality across the defendants.
“The court is entitled to expect to see significant economies of scale,” they argued. “That is plainly not reflected in the levels of costs claimed across the claimants’ budgets. On the contrary, the claimants anticipate deploying a similar level of resources to all of the separately represented defendant groups combined.”
They described the cost submissions as “clear evidence of over-lawyering”.
The full trial to determine liability is scheduled to begin in October. In a rare move, the court has also already set aside time in October 2026 to assess potential damages—though that hearing will not go ahead if the manufacturers are successful in defending the main claim.
A spokesperson for Pogust Goodhead defended the firm’s approach, saying that the defendants’ own costs were of a similar scale and that Pogust Goodhead’s share represented only a fraction of the total fees being claimed by all claimant firms.
Leigh Day declined to comment on the cost dispute.
The case forms part of a wider wave of litigation across Europe and the US following revelations that some carmakers used software to reduce emissions under test conditions, while real-world pollution levels were significantly higher. In the UK, this collective action could run into billions of pounds in potential payouts if successful.
With the October trial fast approaching, scrutiny over the costs of mass litigation—and the business models of firms leading group actions—has intensified. The outcome could set an important precedent for future environmental and consumer-related class actions in the UK.
