As the Diesel Emissions Group Litigation continues to gather momentum ahead of the trial in October 2025, a crucial three-day hearing is about to take place – and it could have a significant impact on the evidence available in court.
This hearing, known as a de-designation hearing, will consider whether key documents—currently protected under strict confidentiality rules—can be made more widely accessible to the claimant legal teams.
What is a CRO?
When the group actions were first launched against Mercedes, Ford, Renault-Nissan, and Peugeot-Citroen, the Court put in place a Confidentiality Ring Order (CRO). This order was designed to protect what the Defendants argued were commercially sensitive documents, including internal communications, test results and technical data about their diesel emissions systems.
Under the CRO, only a very limited number of solicitors from each firm working on behalf of the claimants were allowed to access these documents—and they weren’t even permitted to discuss them with their colleagues.
Why is this now being challenged?
With the 10-week trial scheduled to begin in October 2025, it’s now time for the Court to revisit whether the CRO remains appropriate. The claimants’ legal teams will argue that:
- Much of the information covered by the CRO relates to technology that is over a decade old, which is no longer in commercial use.
- The continued secrecy is unfairly restricting their ability to prepare and present a full case on behalf of the hundreds of thousands of motorists involved.
- Greater transparency is essential to ensure that justice is done—and seen to be done—particularly given the potential scale of wrongdoing being alleged.
The Defendants, on the other hand, continue to claim that the documents contain proprietary information that remains commercially valuable and must be kept confidential to protect their competitive edge.
What happens next?
The Court will now hear arguments from both sides and decide:
- Whether the CRO should remain in place.
- Whether some or all of the documents can be “de-designated”—in other words, no longer treated as confidential.
- Who among the claimant legal teams can access and use the documents in preparing for trial.
This is not just a procedural issue—it goes to the heart of how the trial will unfold, and how much of the car manufacturers’ internal knowledge about diesel emissions systems will be scrutinised in open court.
Why this matters
The outcome of the de-designation hearing could help shine a light on how emissions systems were designed, tested and marketed—raising serious questions about transparency, regulation, and consumer rights. With global interest from regulators and watchdogs, the UK trial could be a turning point in holding manufacturers to account.
“This marks a crucial step in the emissions litigation process,” said Jamie Patton, Managing Director at Johnson Law Group, “where the defendant car manufacturers could finally start to face public scrutiny if the terms of the Confidentiality Ring Order are relaxed. The pressure on the defendants is building.”
At Johnson Law Group, we believe that access to key evidence is essential for a fair trial—and we’re committed to representing our clients with the strongest case possible.