[2025] EWHC 1931 (KB)

This is a further judgment relating to the ongoing management of the NOx emissions litigation, in which cohorts of Claimants bring claims against manufacturer defendants (‘the Manufacturer Defendants’), and others involved in the sale or financing of vehicles. The Claimants allege the existence of illegal ‘defeat devices’ used in tests undertaken by regulators. A 10-week trial in respect of liability, considering sample vehicles across a range of manufacturers (‘the Lead Defendants’), is set down to commence in October 2025 (‘the PDD Trial’) before Cockerill J. Closing submissions, together with an opportunity for other Manufacturer Defendants (who have been referred to as ‘Additional Lead Defendants’ or ‘ALGLOs’) and Non-ALGLO Defendants to make legal submissions, is fixed for March 2026. A 10-week causation and loss trial - the need for which is contingent on any findings of liability - is due to start in October 2026.

One issue with which the parties and the Court have had to grapple throughout is the asserted confidentiality of technologies and strategies which are the subject of scrutiny in this litigation. The Manufacturer Defendants each claim that the divulging of documents which contain proprietary technological know-how either to the other Manufacturer Defendants or into the public arena, and thus making them available to other competitors, could be used to their commercial disadvantage. So far, management of this issue has principally involved a complicated series of confidentiality ring orders between each related claimant and defendant group (referred to as ‘CROs’), and a ‘Pan-NOx’ CRO between the Claimants and the Lead Defendants which, by agreement endorsed by Order of the Court, permits the sharing of disclosure claimed to be confidential to a restricted group of recipients. The CROs contain provisions that permit a party receiving the disclosure, here the Claimants, to seek to have the designation of documents amended, identifying why it is reasonable and necessary for the designation of the document to be amended. The Claimants have sought the de-designation of virtually all documents which are to be contained in the bundle for the upcoming PDD Trial, claiming that the documents are not confidential or should, in any event, be de-designated as non-confidential so as to further open justice. They have also sought the removal of redactions from pleadings and witness evidence where the Lead Defendants have claimed that the contents are confidential.

The Court has already had to consider the de-designation of documents over which a Lead Defendant has claimed confidentiality. The Mercedes Claimants were successful in obtaining (save in one very limited respect) wholesale de-designation of a raft of documents the Mercedes Defendants (‘Mercedes’) had claimed were confidential: see Cavallari v Mercedes-Benz Group AG & Ors [2024] EWHC 190 (KB). Having reviewed the authorities, Cockerill J provided clear guidance on the appropriate approach to be adopted. The Mercedes Defendants thereafter unsuccessfully sought, notwithstanding the de-designation of these documents as non-confidential, an order pursuant to CPR 31.22(2) prohibiting the collateral use of the documents - see the joint judgment of Cockerill J and Constable J at [2024] EWHC 695 (KB). There was a further application pursuant to CPR 31.22(2) by the Mercedes Defendants following the first substantive hearing in this litigation. This was a preliminary issue relating to whether and in what circumstances various decisions by the German authorities were binding on this Court (‘the KBA Issues Trial’). The application targeted, very precisely, particular elements of technical information within much wider documents which had been read by or referred to by the Court during the KBA Issues Trial. The application succeeded in part, principally because the open justice principle was not engaged in circumstances where the information was wholly irrelevant to the public’s ability properly to understand the KBA Issues Trial and Judgment (see Constable J at paragraph [26] at [2024] EWHC 3186 (KB)).

A considerable amount of documentation has been disclosed into the various CROs. Notwithstanding original intentions, the compression of the timetable and the significant burden placed on the Manufacturer Defendants in terms of disclosure, has meant that in practice many documents have been designated as confidential on a ‘precautionary’ basis. Each side criticises the other, either in respect of the quantity of documents placed into the CROs on the part of the Manufacturer Defendants, or the scale and timing of de-designation requests on the part of the Claimants. Resolution of these complaints is not central to this judgment, and in circumstances where the Court is aware of the extent of work being carried out by all parties to meet Court Orders such that the forthcoming PDD Trial remains effective, an overly critical approach to any party would not be justified. Nevertheless, as I make clear below, even when minds have become more focussed, I have been left in no doubt that the Manufacturer Defendants have been over-zealous both to the issue of redactions (of documents and witness statements) and the designation of confidentiality.

That said, save for the Mercedes Defendants, all the Lead Defendants were content, for what they contended were pragmatic reasons coupled with a desire to balance their concerns with the acknowledged importance of open justice, for the majority of the relevant technical data they consider to be confidential, including importantly the parameters and values which are central to the allegations, to be referred to in open court throughout the trial, subject to certain restrictions. To this end, the Lead Defendants’ central proposal at the outset of the hearing was to create a three-tiered categorisation of documentation as follows (the following taken from Ford’s draft Order):

“Green” documents:

(1)

comprise documents and unredacted parts of documents over which no confidentiality is asserted; and

(2)

can be referred to in open court and once referred to will become subject to the collateral use exception in CPR 31.22(1)(a), save that such documents cannot be deployed against another Lead Defendant at the PDD Trial unless such documents are Pan-Lead Documents (as defined in the Pan-Lead CRO).

“Amber” documents:

(1)

are documents which are to be treated for the purpose of the PDD Trial as “confidential in principle” and comprise documents and redacted parts of otherwise “Green” documents, over which confidentiality is asserted;

(2)

can be read out in open court and put on electronic presentation of evidence (‘EPE’) screens;

(3)

pending conclusion of the procedure set out at paragraph 9 of this Order, remain subject to the restrictions on collateral use set out in CPR 31.22, the provisions of the CRO into which they were disclosed and (insofar as applicable) the Pan-Lead CRO; and

(4)

pending conclusion of the procedure set out at paragraph 9 of this Order, do not become part of the publicly accessible court record including for the purposes of CPR 5.4C, and cannot be shared with third parties, or be used for any purpose other than the determination of the respective claims against the Lead Defendants (and, insofar as applicable, used collaterally in accordance with the Pan-Lead CRO), even if they are read to or by the Court, or referred to, at a public hearing, and CPR 31.22(1)(a) shall not apply.

“Red” documents:

(1)

are documents which are to be treated for the purpose of the PDD Trial as being in the “top tier of confidentiality”, and comprise documents and redacted parts of otherwise Green or Amber documents, for which the following procedure is adopted;

(2)

can be read out in court or put on EPE screens when only legal teams and Part 35 Experts for Lead Parties are present in court;

(3)

pending conclusion of the procedure set out at paragraph 9 of this Order, remain subject to the restrictions on collateral use set out in CPR 31.22, the provisions of the CRO into which they were disclosed and (insofar as applicable) the Pan-Lead CRO; and

(4)

pending conclusion of the procedure set out at paragraph 9 of this Order, do not become part of the publicly accessible court record including for the purposes of CPR 5.4C, and cannot be shared with third parties, or be used for any purpose other than the determination of the respective claims against the Lead Defendants (and, insofar as applicable, used collaterally in accordance with the Pan-Lead CRO), even if they are read to or by the Court, or referred to, at a public hearing, and CPR 31.22(1)(a) shall not apply.

Paragraph 9 of the draft Ford Order provided that following the conclusion of the PDD Trial, and to the extent that any Amber or Red document, or any part thereof, had been read to or by the Court, or referred to, during the PDD Trial, the Court would (to the extent it considers necessary and/or upon application) consider to what extent the collateral use restrictions set out above and in the CROs were to be disapplied in those specific instances.

The Lead Defendants, save for the Mercedes Defendants, categorised the parameters and values within the pleadings and other documents (with some exceptions) as Amber. The Mercedes Defendants maintained that the parameters and values should be Red.

Whilst on the Lead Defendants’ proposal, the relevant contents of the ‘Amber’ documents could be read in open court (as could the pleadings, witness or expert evidence which referred to them), the terms of their original draft Order nevertheless imposed restrictions on reporting or other collateral use of the contents of the documents read out until the outcome of the procedure envisaged in paragraph 9. As Mr Kramer KC, for the Claimants, pointed out, this created two problems. The first was one of principle: restrictions on contemporaneous reporting were incompatible with the principle of open justice. The second was one of practicality: it would be confusing and dangerous for different reporting restrictions to apply to different documents. The public or journalists could potentially be in contempt if they failed to understand that, notwithstanding a particular document being referred to in open court, a document’s contents could not be reported. Constant warnings for some documents or some parts of some documents would be cumbersome, and may be ineffective where the public or journalists attended only parts of the trial.

By the conclusion of the three-day hearing, this proposal had undergone some revision. Mr Sage on behalf of the Renault Defendants accepted - largely with support of the other Lead Defendants– that whilst the Amber category should be maintained, the reading of part of an Amber document in open court would have the ordinary consequences in that its contents could be reported or disseminated by any member of the public or a journalist attending. The only restriction to the usual application of CPR 31.22(1)(a) in respect of an Amber document was that the loss of protection against collateral use was restricted to that part of the document, rather than the whole document. The practical distinction between how a Green document and an Amber document was treated at trial, and how its contents could be reported, substantially dissolved.

The Lead Defendants, notwithstanding this concession, maintained their objection to the Claimants’ application to remove the redactions on pleadings. The effect of this was that, although a party or journalist could learn the various parameters and values claimed to lie at the heart of the alleged PDDs by attending the trial itself, this information would not otherwise be publicly available. Alongside the Claimants’ application in this respect are applications by three interested parties, ClientEarth, Mums for Lungs, and the Scottish NOx Emissions Steering Group (‘the Interested Parties’) for unredacted copies of the pleadings pursuant to CPR 5.4C(1). As explained further below, it is the detailed technical information central to the allegations made which has been redacted, and there is therefore considerable overlap between the Interested Parties’ applications and those made by the Claimants. If the Interested Parties succeed, and the relevant parameters and values are therefore made public through the pleadings, there would plainly be no remaining confidentiality in the related parts of the disclosure which contain the same information.

It is for this reason that I consider the application by the Claimants, and the Interested Parties, for unredacted versions of the pleadings first, after setting out the relevant law. Thereafter I consider the applications relating to documents in respect of which the Interested Parties had no direct involvement.