Warning letters in public inquiries

28th June 2023

For the next instalment of our public inquiries article series, we are looking at Warning Letters.

Rules 13-16 of the Inquiry Rules 2006 (“the Rules”) set out the requirements for Warning Letters.

What is a Warning Letter?

During the course of the evidence given to an Inquiry, whether that be written evidence, oral evidence or documents disclosed to the Inquiry, it is inevitable that criticisms will be made of individuals or organisations. Consequently, the Chair may make findings or conclusions based on those criticisms or indeed the Chair’s findings or conclusions may raise the criticism.

Warning Letters, often referred to as ‘Maxwellisation’ or ‘Salmon Letters’, ensure that witnesses or organisations have a fair opportunity to respond to criticism raised of them during the course of the Inquiry or criticism that the Chair proposes to include in any report.

Whilst the Chair has discretion to send a Warning Letter, Rule 13(3) states that if a Warning Letter is not sent and the recipient has not been given a reasonable opportunity to respond then criticism of an individual or an organisation cannot be included in any report published by the Inquiry.

Who may receive a Warning Letter?

Rule 13 (1) states that the Chair may send a warning letter to any person:

  • a) they consider may be, or who has been, subject to criticism in the inquiry proceedings; or
  • b) about whom criticism may be inferred from evidence that has been given during the inquiry proceedings; or
  • c) who may be subject to criticism in the report, or any interim report.

If an individual or an organisation receives a Warning Letter then the Inquiry must disregard this fact when determining the weight of any evidence given by that individual or organisation (Rule 16).

What will a Warning Letter include?

Pursuant to Rule 15(1) the following information must be included in a Warning Letter:

  • a) state what the criticism or proposed criticism is;
  • b) contain a statement of the facts that the chairman considers substantiate the criticism or proposed criticism; and
  • c) refer to any evidence which supports those facts.

The following requirements are not applicable where the Warning Letter is sent on the basis that the criticism may be inferred from evidence given (Rule 13(1)(b)) however, if this is the case the letter must refer to the evidence where the criticism may be inferred.

The content of a Warning Letter is subject to any restrictions on the disclosure of evidence, documentation or information in accordance with Section 19 of the Act (Restrictions on Public Access), Section 23 of the Act (Risk of damage to the economy) or where there has been a determination of public interest immunity.

If any evidence is referred to within the Warning Letter then the Chair may provide copies of the evidence referred to if considered appropriate to do so.

Is the content of a Warning Letter confidential?

In accordance with Rule 14, the contents of a Warning Letter are subject to an obligation of confidence which is owed:

  • a) separately by each member of the inquiry team to the recipient of the Warning Letter;
  • b) by the recipient to the Chair; and
  • c) by the recipient’s recognised legal representative to the Chair.

This means the content of the Warning Letter is not disclosable to any other party (including other witnesses or core participants) or the public in general however, the recipient is permitted to share the Warning Letter with their legal representative pursuant to Rule 13(2). The obligation of confidence can be waived in writing by the Chair and/or the recipient of the Warning Letter at any time.

The obligation of confidence is not indefinite. The Inquiry panel’s obligations cease when the Inquiry report is signed (in accordance with Section 24(4)) and all other obligations of confidence cease when the report is published.

The Rules do not provide any specific requirements for issuing Warning Letters or for how responses should be provided. Guidance or a protocol document is often issued by the Chair of the particular Inquiry which sets out the arrangements for issuing Warning Letters and steps that recipients are required to adhere to when issued with a Warning Letter.

Public inquiries series

In our series of blogs on public inquiries, we have also looked at:

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