Public Inquiries: A Quick Guide for Potential Witnesses

Public Inquiries: A Quick Guide for Potential Witnesses

Blog WilmerHale W.I.R.E. UK

This article has been republished by Expert Witness Journal.

Public inquiries have consistently made headlines in recent months.  This type of inquiries typically focuses on major incidents that have significantly impacted a large number or group of people.  They often involve vast amounts of documentary evidence and numerous witnesses.  Additionally, public inquiries differ from ordinary criminal or civil proceedings in that they seek to establish facts rather than attribute liability: they are inquisitorial rather than adversarial in nature. Nonetheless, giving evidence in an inquiry can be a daunting prospect.  This guide aims to provide an introduction to public inquiries for the benefit of those who have been involved in events under examination by an inquiry and might therefore be contacted to give evidence.

What are statutory public inquiries?

Statutory public inquiries are inquiries established at the request of a Minister under the Inquiries Act 2005 (“the Act”) and governed by the Inquiry Rules 2006 (“the Rules”).  The purpose of a statutory inquiry is to investigate particular events that have caused public concern. They seek to establish what events have happened, why they have happened, who is responsible for them happening, and what can be done to prevent similar events from happening in the future.

Ongoing statutory inquiries include, for instance, the Post Office inquiry, which is examining the circumstances in which hundreds of subpostmasters were wrongly prosecuted and convicted in relation to (or otherwise impacted by) accounting shortfalls caused by the Post Office’s accounting system; the Grenfell Tower Inquiry, which is looking at the circumstances surrounding the Grenfell Tower fire in June 2017; and the Manchester Arena Inquiry, which is investigating the circumstances surrounding the Manchester Arena terror attack in 2017. 

Statutory inquiries are conducted by an inquiry panel led by a chairman appointed by the Minister.1  The chairman and any other panel members are often judges, coroners, or professionals with relevant knowledge or expertise.  They are supported by counsel, a solicitor, a secretary, assessors, and administrative, legal, and managerial staff.  The inquiry panel will gather, review, and hear evidence from various sources and witnesses to determine the issues in question in the inquiry. Based on this evidence, the panel will produce a report, which will be submitted to the Minister and laid before Parliament.  It is not uncommon for inquiries to take years to produce a report – twelve in the case of the Bloody Sunday inquiry.

What can the inquiry panel ask witnesses to do?  

The chairman of a statutory inquiry has powers to compel witnesses to give evidence.  Specifically, the chairman may by notice require a person to provide a written statement, produce documents, or give oral evidence in interview or at a hearing in relation to any issue in question in the inquiry.2  Such notice may be delivered to the witness in person, or sent to the person’s designated postal address, fax number, or email address (which can be the address or number of their solicitors).3

The powers of the chairman are limited to information that could be disclosed in civil proceedings. In other words, the chairman cannot require a person to produce privileged documents or information, documents or information protected by public interest immunity,4 or evidence that would lead to self-incrimination.5

Can a witness refuse to give evidence?

Failing without reasonable excuse to do anything that is required in a notice is a criminal offence punishable by a fine and/or 51 weeks’ imprisonment under the Act.6 Doing anything to distort or alter evidence provided to an inquiry, to prevent evidence from being provided to an inquiry, or to destroy or conceal documents relevant to an inquiry, are also offences under the Act.7  

In some cases, however, it may be appropriate for the recipient of a notice to claim that they are unable to comply with the notice, or that it is unreasonable to require them to comply with the notice.8  In addition to the categories of information that the chairman cannot require (outlined above), a claim may be made where:

  1. The recipient of the notice is not in possession of, and cannot access, the documents or information requested in the notice;
  2. It would be too difficult, take too long, or be too expensive for the recipient to comply with the notice;
  3. The documents or information requested are not relevant to the Inquiry’s terms of reference;
  4. The chairman has not acted with fairness and with regard to the need to avoid any unnecessary cost in making the request.9

The claim will be determined by the chairman, who may revoke or amend the notice in response.  For instance, the chairman may refine an excessively broad request for information or allow documents to be produced with redactions. In determining the claim, the chairman must consider the public interest in the documents or information being provided to the inquiry, having regard to the likely importance of the information.  Alternatively or additionally, the recipient of a notice may consider the possibility of applying to the inquiry for a restriction order to protect their anonymity.    

A recipient whose claim or application is refused, and who fears that complying with a notice will force them to disclose incriminating evidence, will have to balance the risk of prosecution under the Act and the risk to their reputation if they fail to comply, with the risk of being investigated and prosecuted for further offences on the basis of that evidence.  (The use of evidence provided to an inquiry in civil or criminal proceedings is discussed in more detail below.)

Can witnesses see evidence given to the inquiry by others?

A witness’s rights to access the evidence provided to the inquiry will vary depending on their status.  “Core participants” are persons who have played a significant role or have a significant interest in the events to which the inquiry relate, and have been designated as such by the chairman.  Those with core participant status will usually be given access to relevant documentary evidence collated by the inquiry, subject to potential restrictions imposed by the chairman.  They will also receive a copy of the inquiry report before its publication (but after its delivery to the Minister).10  

Those who have not been designated as core participants will have the same rights of access as any other members of the public.  They will be able to watch inquiry hearings live, review hearing transcripts, and read the statements of witnesses who have already given oral evidence at a hearing.  They will not have access to the documentary evidence provided to the inquiry.

Can witnesses’ evidence be used in civil and criminal proceedings against them?

An inquiry has no power to determine any person’s civil or criminal liability.11  However, liability may be inferred from the facts that the inquiry determines or the recommendations that it makes. 

There is no general rule prohibiting the use of evidence given in an inquiry in civil or criminal proceedings.  As discussed above, a witness cannot be compelled to provide documents or give oral evidence that would be self-incriminatory and may oppose a notice on those grounds.  Alas, the line between incriminatory evidence and evidence that might assist a criminal investigation is often blurry, and the chairman and witness may disagree on where it lies. 

In some inquiries, the privilege against self-incrimination may be required to be waived.  The Attorney-General will then issue an undertaking that evidence given by a witness in the inquiry will not be used in criminal proceedings against them.  However, the protection afforded by such undertakings can be limited: its scope will vary with the wording of the undertaking.  For instance, an undertaking might prohibit the use of evidence in a criminal trial and the charging decision-making process, but not in the preliminary stages of an investigation. Regardless of the undertaking, media coverage of any potentially incriminating evidence may also influence a jury in subsequent proceedings.       

These difficulties are compounded where an inquiry and civil or criminal proceedings run concurrently.  While the chairman has the power to suspend an inquiry to allow for the completion of any other investigation or proceedings, it will often be in the public interest for the inquiry to progress without delay.  As an alternative to suspension, the chairman may organise the inquiry in a way that limits the use of inquiry-derived evidence in other investigations or proceedings: for instance, the chairman may choose to focus on issues irrelevant to the criminal investigation in early phases of the inquiry, or may delay the publication of the report.  A witness involved (or who expects to become involved) in concurrent proceedings may consider making submissions to that effect to the inquiry.

An inquiry panel must not include any explicit or significant criticism of a person in the report unless the chairman has sent that person a warning letter and given them a reasonable opportunity to respond.  A warning letter is a letter that outlines the proposed criticism and the facts and evidence supporting it.  It will be particularly important for a witness to thoroughly address any criticism that may give rise to allegations of criminal conduct or to a civil claim.

Do witnesses need a solicitor?

A solicitor with experience in public inquiries can assist in many ways.  They will typically review any available documents relevant to the inquiry, help their client articulate their own account of the facts in question in the inquiry, follow inquiry hearings, handle communications with the inquiry, prepare claims opposing notices and applications for anonymity where appropriate, draft witness statements, and respond to warning letters. In instances where the client is a company, charity, or public body, a solicitor will advise on the preservation and production of documents requested by the inquiry.  Crucially, they will also advise on any risk of criminal or civil liability arising from their client’s participation in the inquiry. 


1 Inquiries Act 2005, s.3-4.

2 Inquiries Act 2005, s.21.

3 Inquiry Rules 2006, r.3.

4 Public interest immunity protects material whose disclosure would be harmful to the public interest.  For instance, material relating to national security, diplomacy, or criminal intelligence, may be protected by public interest immunity.

5 Inquiries Act 2005, s.22.

6 Inquiries Act, s.35.

7 Inquiries Act, s.35.

8 Inquiries Act, s.21(4).

9 Inquiries Act 2005, s.17.

10 Inquiry Rules 2006, r.17.

11 Inquiries Act 2005, s.2.

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