Parallel Proceedings

A party to parallel proceedings has access to a range of documents and evidence from a number of different sources.

What case material can be used for the purposes of defence?

As a matter of public policy, the use of evidence and disclosed material is restricted to that which is necessary to secure justice in the relevant proceedings.

A party is therefore generally not permitted to use such material for a purpose that is different or collateral to those proceedings, including for related proceedings, in the absence of certain exceptions being met. This can be challenging in the context of parallel proceedings where evidence and disclosure served in one action may be relevant to another.

A party seeking to use evidence or disclosure received in one action for the purposes of another must secure the required consents or permission before doing so and, in the interim, adopt practical measures to minimise the risk of inadvertent breach.

Other categories of document which are held on the Court file may be accessed and used by interested third parties, including for the purposes of prospective or ongoing related proceedings. To avoid undermining its case, a party to multiple proceedings should ensure its position is consistent in all documents filed with the Court.

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Limitations on use
  • Civil proceedings

    Documents disclosed or witness evidence served on a party to civil proceedings (including information contained within them) cannot be ‘used’ by that party for the purposes of other proceedings unless:

    • the documents have been read to or by the Court or referred to at a hearing in public (see here for a discussion of the scope of this exception, and in particular how it may be applied to documents and evidence referred to at an aborted trial)
    • the court gives permission, or
    • the disclosing party and (if different) the document owner, or the relevant witness, agrees (see CPR 31.22(1) and CPR 32.12).

    The meaning of "use" in this context is very broad and even includes reviewing a document if the purpose of such review was a collateral one (Tchenguiz & another v Grant Thornton LLP & others). For further information on how the meaning of "use" has been interpreted by the Courts see our article.

    These rules recognise that disclosure is an invasion of a litigant’s right to privacy and confidentiality that ought to be limited to what is necessary to achieve justice in the proceedings. The provisions also serve to encourage parties to comply with their disclosure obligations.

    A deliberate or reckless breach of the rules may be treated as a contempt of Court (Grosvenor Chemicals Ltd and others v UPL Europe Ltd and others). An accidental but serious breach can also result in serious criticism of a party and/or its legal advisers (The ECU Group PLC v HSBC Bank PLC and others).

    Criminal proceedings

    The rules governing the use of disclosed material and evidence in criminal proceedings are derived from several sources including the Criminal Procedure Rules, Criminal Procedure and Investigations Act 1996 and case law. They are less well developed than their civil equivalents, largely as a consequence of the fact that extended prosecution disclosure obligations are a relatively recent phenomenon.

    However, it is generally accepted that similar principles apply to the collateral use of documents disclosed to a defendant in criminal proceedings (including unused and case materials) as to disclosed material and witness statements in civil proceedings - typically such material can be used for related proceedings only where it has been referred to in open Court, or with the Court’s permission. Notwithstanding that, the public interests justifying the limitation on the use of such materials are different to those which underpin the civil rules. The primary concern in the criminal sphere is to ensure that the privacy and confidentiality of third parties who assist the authorities by providing information or witness evidence is not invaded any more than is necessary for the purposes of justice.

    An important difference to note is that no collateral use restriction applies to the prosecution, who is free to disclose material gathered for the purposes of a prosecution to any person, including for the purposes of related civil proceedings, where it is in the interests of justice to do so. However, where the material was originally obtained under compulsion from third parties who do not consent to its further use, the prosecution is unlikely to allow others to use it without a Court order being made.

    Regulatory proceedings

    Limitations on the use of disclosed documents or witness evidence may be imposed on parties to regulatory proceedings if provided for in the relevant governing rules. Such limitations may be expressed in terms of a prohibition against collateral use, or as a requirement to keep certain information confidential.

    By way of an example, similar limitations to those that apply in the context of civil proceedings are included in the Accountancy Scheme and Accountancy Regulations, which govern investigations and proceedings brought by the Financial Reporting Council against members of the accountancy profession. Consistent with the position in both civil and criminal proceedings, these limitations on use do not apply to any documents or information which are in the public domain, or which have been disclosed at a public hearing. This exception recognises the common law principle of open justice and is likely to apply across most (if not all) types of regulatory proceedings. It is also commonly the case that material related to an investigation or proceedings can be used for another purpose if the owner of the document or (where applicable) the author of the statement agrees, and/or where any confidentiality that applies to the document has been waived.

Seeking permission
  • Civil proceedings

    Where a party is unable to rely on any of the exceptions to the rules against collateral use it may seek the Court’s permission to use documents disclosed or evidence served in civil proceedings for the purposes of related proceedings by making an application pursuant to CPR 31.22(1)(b)/CPR 32.12(2)(b). Such an application will be granted only if there are special circumstances which constitute a cogent reason for permitting collateral use. Whether such circumstances exist is highly fact dependent, including the particular use to which the document is intended to be put and the balance of any competing public interests before the Court. 

    Case law...

    Interesting points to note from the relevant case law include the following:

    • where documents are sought to be used for the investigation and prosecution of criminal proceedings by a public authority such as the SFO, the public interest in allowing those proceedings to continue is likely to outweigh the concern to control the collateral use of disclosed documents (Marlwood Commercial Inc v Kozeny)
    • arguments in favour of use are likely to be most persuasive where the subject matter of the proceedings are closely linked, and the material is highly relevant to the related proceedings in which it is sought to be used (Tchenguiz v SFO)
    • where the collateral use to which documents disclosed in other proceedings are to be put is of a limited nature, such as reviewing and obtaining legal advice in respect of them, the court is more likely to grant permission (Tchenguiz v SFO; The Libyan Investment Authority v Sociéte Generale S.A. and others)
    • Using disclosed documents for the purposes of considering whether to join a new party to existing proceedings is not a collateral use (Grosvenor Chemicals Ltd v UPL Europe Ltd);
    • the Court has the power to grant permission retrospectively in respect of a prior use of documents in breach of CPR 31.22(1) but such permission will only rarely be granted (Miller v Scorey [1996] 1 WLR 1122).

    Criminal proceedings

    Where documents or information derived from unused materials disclosed by the prosecution in criminal proceedings have not been referred to in open Court, pursuant to s.17(4) CPIA and CrimPR 15.7 an application may be made by a defendant at any time (including after those proceedings have concluded) for permission to use them for a collateral purpose. This includes for the purposes of parallel, proceedings.

    There is no equivalent statutory basis for an application by the defendant for permission to use material relied on as part of the prosecution case (so-called "used" or case materials). However, it is generally accepted that such material is subject to an implied undertaking against collateral use unless and until it is referred to in open court. A party seeking to use it for a collateral purpose would therefore be advised to make an application for the Court’s permission to do so.

    We are not aware of any specific authority on the meaning of "use" in this context but we consider it likely that a criminal Court would take an expansive view, guided by the decisions of the civil Courts in the context of CPR 31.22/CPR 32.12.

    Regulatory proceedings

    As above, a party seeking to use for other purposes documents or information which it has acquired during the course of regulatory proceedings will need to look to the governing rules of the relevant regulatory body or Tribunal for any restrictions that apply. Such rules may also set out the process a party should follow in seeking to lift or vary any such restriction.

    In the event that no specific route for doing so is prescribed within the relevant rules, a party may wish to seek direction from the Court or Tribunal as to how to proceed by means of an application pursuant to its general case management powers.

    Where the rules contain no express restrictions as to the use of documents or information acquired during regulatory proceedings, a party may elect to use the material for the intended collateral purpose (including for the purposes of related proceedings) without taking any further step. However, given the limitations that apply to the use of disclosed material and evidence in civil and criminal proceedings, a decision to proceed in this way may be challenged by the regulator or the party who disclosed or served the documents or statements on the basis that it is in the public interest to restrict their wider use.

Access to file
  • Various documents generated during proceedings may be held by the Court or Tribunal on a case file. In certain circumstances, this material may be accessed and used by interested parties for other purposes. Often, it is a particularly useful source of information for parties involved in related, including parallel, proceedings.

    With that in mind, it is important for those facing multiple proceedings to ensure consistency in documents filed with the Court - any tensions or inconsistencies can be exploited by an opponent and may undermine their case. This possibility is not solely the preserve of private parties, for example the SFO may apply to access material from the Court file in a civil case, for use in a criminal investigation or proceedings.

    Some classes of material are publicly available and accessible upon request and others will be made available only by order of the Court following an application (for further information see CPR5.4(C), CrimPR 5.8 and Criminal Practice Direction I (General matters) 5B). The justification for allowing access is that open justice requires documents which form part of the Court’s decision-making process, as well as any order or judgment made following a public hearing, to be available. There are exceptions to this but they have to be justified by some even more important principle.

    When determining applications for access to documents on the Court file, the Courts will weigh the public interest in open justice and the interests of the party seeking access (including the purpose for which the material sought is required), against the private interests of the parties to the proceedings and any specific objections they raise. Documents whose contents have been read out in open Court, or are treated as though they have been (such as documents read by the Judge), should generally be made available.

    An application for access to material on the Court file for use in related proceedings will most commonly be made by an interested third party (i.e. not a party to the proceedings). Where a party to proceedings seeks to use material served by its opponents and lodged on the Court file for the purposes of a related action it should make an application for the Court’s permission to use them for a collateral purpose (see Handling case material: seeking permission. Alternatively, a party may seek specific disclosure of documents filed by an opponent in related proceedings, where they are known to be in their possession and are expected to meet the relevant test.

    Access to documents on the Court file may be restricted by an order of the Court, where it is in the interests of justice to do so. Any restriction imposed will be limited to that which is necessary and proportionate in the circumstances of the particular case. If it is possible to address the interests of an applicant by some lesser measure, such as the redaction of certain information from the documents on file, the Court will generally prefer that course of action.

    Tribunals hearing regulatory proceedings may maintain a Court file from which an interested party could seek to obtain documents. However, this will not always be the case - for example, the Upper Tribunal (Tax and Chancery Chamber), which hears contested proceedings brought by the FCA, does not maintain a Court file or have in place a formal process by which an interested party can seek access to case material.

    A request for access to material can be made by an interested third party to a judge hearing proceedings, who will consult with the relevant parties. However, where they object to the material being made available (often the case), the judge will typically refuse to grant access.

Kirsten Kitt, Managing Associate

The quality and accuracy of any investigation depends on the quality and range of information and documentation obtained, often from multiple sources. But the consequences for improper handling of information can be grave, and compelling - sometimes conflicting - obligations in case material can be very complex to manage. Predicting information flaws and related obligations from the start will be critical in preventing inadvertent breaches of rules and duties.


This document (and any information accessed through links in this document) is provided for information purposes only and does not constitute legal advice. Professional legal advice should be obtained before taking or refraining from any action as a result of the contents of this document.