A practical guide to commissioning and conducting investigations and inquiries | Fieldfisher
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A practical guide to commissioning and conducting investigations and inquiries

Martin Smith


United Kingdom

This practice note provides an introduction to the substantive issues and law relating to the commissioning and conduct of investigations and inquiries.

This article was first published in Practical Law Company in December 2008. 

Practice note

This practice note provides an introduction to the substantive issues and law relating to the commissioning and conduct of investigations and inquiries.  Ed Marsden (managing director, Verita) and Martin Smith (partner, Fieldfisher).

Investigations and inquiries in context

Investigations and inquiries are an increasing feature of public life.  They come in a variety of forms. Some have formal powers while others are carried out on an ad hoc, informal basis. Some are triggered by government policy while others are commissioned at the discretion of the government and/or public bodies.

Certain procedural and legal issues arise in all investigations and inquiries. It is important to get these right so that the investigative process runs smoothly, individuals are treated fairly & lawfully and the budget/timetable is maintained. 

This note sets out what these issues are. Organisations intending to commission an investigation or inquiry should seek professional advice and assistance at the outset.


  1. Why is an inquiry needed?
  2. Who should commission the inquiry and have they authority to do so?
  3. Considering the impact of other inquiries
  4. Does the inquiry need powers or not?
  5. The Inquiries Act 2005
  6. Writing terms of reference
  7. Retrieving and safeguarding evidence
  8. Appointing a chair, panellists and expert advisers
  9. Managing the inquiry process
  10. Managing and caring for witnesses
  11. Salmon letters & Maxwellisation
  12. Defamation and qualified privilege
  13. Data protection
  14. Disclosure
  15. Communicating the findings of an inquiry

1. Why is an inquiry needed?

Public bodies commission inquiries as a remedy to a failure/complaint or in response to an act of omission or commission. An inquiry - usually carried out by individuals independent of the body being investigated - is a means of establishing an independent account of the facts, circumstances and reasons as to why something went wrong. Inquiries usually make recommendations about how organisations can improve their performance. 

The scale and nature of the inquiry depends on circumstances.   Matters of serious public concern may be investigated in a formal and legalistic manner with the inquiry panel headed by a senior lawyer such as a judge, witnesses allowed legal representation and parties permitted to cross-question some witnesses. Although such processes are in fact inquisitorial in nature, they can sometimes appear to be more like normal adversarial court proceedings. This form of investigation is usually commissioned under the Inquiries Act 2005.

Investigation of lesser matters is usually carried in a more informal manner albeit that the investigative procedure is rigorous. Typically, these inquiries are carried out by appropriately qualified, independent individuals who ask questions of invited witnesses in order to establish the facts and circumstances being investigated.  Individuals are not allowed legal representation and there is no opportunity to cross-question. 

Some inquiries are triggered by government policy/guidance or legislation. For example, local safeguarding children boards commission an independent investigation (serious case review) where children have been killed or seriously harmed. NHS strategic health authorities are obliged by guidance to commission an independent investigation when a patient in the care of mental health services is convicted of committing a homicide. 

Public bodies and government sometimes commission investigations in response to public concern expressed by victims, families, relatives, the media and politicians e.g. Bloody Sunday and the sinking of the MV Derbyshire off Japan in 1980. The purpose is to help allay public concern, restore confidence and ensure a proper account is given of a significant event. A change in government also often prompts the commissioning of inquiries into high-profile events that occurred during the life time of the previous administration. Inquiries commissioned by government ministers are usually conducted under the Inquiries Act 2005.

Ad hoc, informal inquiries are sometimes commissioned by public bodies as a substitute for local management action. Generally speaking, this is an inappropriate use of an inquiry and organisations should be encouraged to follow established local policies and procedures instead.


2. Who should commission the inquiry and have they authority to do so?

Most public bodies have the authority to commission an inquiry into their own activities. Legal advisers should be consulted if there is any doubt about the commissioning body’s power to do so. Those being asked to undertake the inquiry should first make sure that their commissioning body has such authority as an inquiry which is ultra vires may not benefit fully from the qualified privilege usually enjoyed by investigators (see section 12).

Those commissioning an independent inquiry should not be implicated in the matter to be investigated. They should stand aside if they are. Ideally, those commissioning the inquiry should not be material witnesses. Rather the commissioners should be at arms length so as to ensure the integrity of the investigation and to avoid circumstances where those conducting the investigation can be put under improper pressure.


3. Considering the impact of other inquiries

Serious incidents may result in a number of inquiries all with a different remit, for example inquiries by the police, regulators and inspectorates. Those commissioning an inquiry may want to discuss their proposed investigation with these organisations before it gets underway. Where criminal offences are suspected the police are likely to claim primacy and there may be a tension between the need to conduct an effective and urgent inquiry and the possibility of compromising evidence required by the police. With close coordination and cooperation between the various investigation teams, these difficulties are usually avoided. There are national agreements in place between some organisations about these matters. For example the 2006 memorandum of understanding between the National Health Service, Association of Chief Police Officers and the Health Safety Executive entitled Investigating patient safety incidents involving unexpected death or serious untoward harm: a protocol for liaison and effective communications and its accompanying NHS guidelines.


4. Does the inquiry need powers to compel production of evidence or not?

Most inquiries rely on the cooperation of organisations and individuals to carry out their work and have no authority to compel the production of documents or the attendance of witnesses for interview. In these circumstances, it is often helpful for the person leading the organisation to make clear to all staff that their cooperation is expected and by these means it is usually possible to carry out an effective inquiry without such powers. The Hutton Inquiry is an example of a high profile, ad hoc public inquiry which proceeded without powers to compel evidence.

Some circumstances warrant an inquiry that has the authority and power to require production of evidence, for example where someone has died as a result of the actions/inactions of an agent of the state or where it is expected that an organisation will not cooperate. In such cases it is best if those commissioning the inquiry grant it formal powers at the outset so that its work can be carried out properly. Granting such powers part way through an inquiry can result in changes to the procedures or the need to appoint a legally qualified chair.

Investigators should discuss any concerns they have about their ability to conduct an effective inquiry with their commissioning body at the earliest opportunity. Failure to carry out an effective investigation can lead to legal challenge. Investigators should discuss any concerns they have about their ability to conduct an effective inquiry with their commissioning body at the earliest opportunity. A practical and effective investigation is a requirement of Article 2 of the European Convention on Human Rights where a person has died possibly as a result of the actions of the state.

Case study
In Edwards v UK (2002) 35 EHRR 19, a psychiatrically disturbed prisoner had been placed in a prison cell with another prisoner who was displaying symptoms of bizarre behaviour and he was killed by him as a result of their being locked up together. The state authorities appointed a distinguished panel, headed by a QC, to conduct a private non-statutory inquiry. The ECtHR praised the inquiry report as follows: “The inquiry report, which ran to 388 pages, reached numerous findings of defects and made recommendations for future practice. It was a meticulous document, on which the Court did not hesitate to rely in assessing the facts and issues in the case”. 

However, the ECtHR held that obligations imposed by Article 2 ECHR had not been complied with, in part because the inquiry had not had power to compel the attendance of witnesses. As a result, the inquiry had not taken evidence from two witnesses whose evidence may have been crucial to determining the facts of the case.

5. The Inquiries Act 2005

The Inquiries Act 2005 received Royal Assent on 7 April 2005 and came into force on 7 June 2005.  It seeks to create a statutory framework for inquiries into matters of public concern established by ministers. It replaced over 30 different pieces of legislation on inquiries, consolidating much of the current legislation and codifying past practice.

The government has stated that the Act will only be used for inquiries that need to have statutory powers (for example to compel the attendance of witnesses or production of documents). There will, however, still be a place for non-statutory inquiries.

Key provisions of the Act are as follows:

  • Section 1: Power to establish inquiry
  • Section 3: To be conducted by chairman alone or chairman plus wing members
  • Section 11: Power to appoint assessors
  • Section 13: Minister’s power to suspend inquiry
  • Section 15: Powers to convert another inquiry into an inquiry under the Act
  • Section 17(2): Power to take evidence on oath
  • Section 18: Power to compel attendance to give evidence and production of documents
  • Section 37: Immunity from suit
  • Section 38: Time limit for judicial review of inquiry decisions reduced to 14 days
  • Section 40: Power for chairman to reimburse expenses to persons in connection with the inquiry

Examples of inquiries conducted under the Act include the E-Coli Inquiry and the Baha Mousa Inquiry.

Under section 17 of the Act, the procedure and conduct of an inquiry are matters for its chairman, subject to any provision of the Act itself or any rules made under it, the requirements of fairness and the need to avoid unnecessary cost.  Procedural rules have been made under section 41 of the Act (The Inquiry Rules 2006) and make provision in respect of the following matters:

  • service of documents
  • designation of core participants
  • legal representation
  • evidence
  • disclosure
  • warning letters
  • reports
  • records management
  • awards in respect of expenses and costs

6. Writing terms of reference

Terms of reference are the foundation stone of a successful inquiry.  Terms of reference need to be written and should set out who is commissioning the inquiry and by what authority. They should explain the purpose of the inquiry but also the limitations e.g. if the inquiry has no disciplinary remit then this should be made clear. The terms of reference should make it clear if the investigators are expected to produce a written report with recommendations. They should include a timetable and should say whether the outcome of the inquiry is to be published and whose decision and responsibility this is. Organisations should not commit to full disclosure of the report at the outset of the investigation.

Those doing the inquiry – especially the chair or lead investigator – need to understand their remit and what the commissioners of the inquiry consider to be included in it (and outside it). To that end, it is a good idea to include the chair or lead investigator in drafting the terms of reference.

Those commissioning an inquiry should show terms of reference to their legal advisers before they are finalised.

7. Retrieving and safeguarding evidence

Inquiries rely on documents and testimony to be effective and get to the bottom of what has happened. Finding and securing documentation is a major task at the outset of any inquiry and always made more complex when time has elapsed. 

Commissioners or investigators should recover and keep safe all relevant documents and records as soon as possible and particularly in cases where it is believed that documents are at risk of being destroyed or mislaid. This minimizes loss or changes after the event.  It avoids the inquiry being delayed and helps ensure that the investigators are able to establish the truth about a matter. A log should be kept of what is recovered and where from. Thought also needs to be given to interrogating electronic systems for documents.

In cases where the investigators need access to personal information e.g. medical records then consent from the individual concerned is needed.

8. Appointing a chair, panellists and expert advisers

It is important to select the members of the inquiry team carefully and with an eye to the skills and expertise needed to carry out an effective investigation. The credibility of the inquiry will depend on these people. Ideally, the chair or lead should be involved in the appointment of the other team members.

In selecting the inquiry team commissioners should ensure that individual members:

  • have the necessary skills, knowledge, independence and experience
  • do not face a conflict of interest
  • have sufficient time available

Each investigator and adviser should be provided with a letter of appointment and a job description. The letter of appointment is likely to need to contain a carefully worded indemnity to protect the investigator from legal proceedings arising from the inquiry. 

9. Managing the inquiry process

All inquiries need to be properly managed and administered and people should be appointed to this task. Complex inquiries need to be managed by senior, experienced individuals who understand what is to be investigated and the procedural rules that will apply.

Key tasks in managing the investigative process are:

  • preparing procedural rules for the inquiry
  • drawing up a budget and timetable
  • locating and recovering all necessary documents including relevant policies and procedures
  • preparing documents for the inquiry team
  • making contact with potential witnesses
  • managing and caring for witnesses
  • seeking appropriate consents for accessing personal information
  • handling all inquiry correspondence
  • organising witness interviews including accommodation for these
  • arranging recording and transcribing service
  • liaising with the commissioning body
  • handling media enquiries (with appropriate professional advice)
  • preparing the report

10. Managing and caring for witnesses

The procedure followed by the inquiry is vital to its integrity and the investigators are responsible for it. The guiding principles for an inquiry team are fairness and reasonableness above speed and economy.

Investigators should explain at the outset to witnesses what it is that they have been commissioned to do and how they will go about doing it. Those invited to interview should be sent a letter setting out what it is that they will be asked about. The letter should include the terms of reference and the procedural rules. Witnesses should be offered the opportunity to bring a friend or legal representative to their interview though it should be made clear that the investigators’ questions will be directed to them.

Witnesses should be sent the written transcript of their evidence and be given the opportunity to make amendments and additions to it.  Those criticised should be allowed to see any criticisms and offered the chance to comment on them before the report is finalised. The inquiry team should take proper account of any comments they receive. In some circumstances witnesses should be sent the entire report to comment on e.g. where the whole report reflects on the actions of a senior individual in an organisation. This aspect is discussed in further detail in section 11 below.

11. Salmon letters & Maxwellisation

Following dissatisfaction with procedural aspects of Lord Denning’s inquiry into the Profumo Affair, Lord Justice Salmon chaired a Royal Commission on Tribunals of Inquiry. He subsequently published a report setting out his findings in 1966. This contained reference to six cardinal principles of fair procedure under the Tribunals and Inquiries Act 1921 which came to be known as the “Salmon principles”.
The Salmon principles 

Before any person becomes involved in an inquiry, the tribunal must be satisfied that there are circumstances which affect him and which the tribunal proposes to investigate.

  1. Before any person who is involved in an inquiry is called as a witness he should be informed of any allegations which are made against him and the substance of the evidence in support of them.
  2. (a) He should be given an adequate opportunity of preparing his case and of being assisted by legal advisers.
    (b) His legal expenses should normally be met out of public funds.
  3. He should have the opportunity of being examined by his own solicitor or counsel and of stating his case in public at the inquiry.
  4. Any material witnesses he wishes called at the inquiry should, if reasonably practicable, be heard.
  5. He should have the opportunity of testing by cross-examination conducted by his own solicitor or counsel any evidence which may affect him.

An aspect of principle 2 above was that following the Salmon Report, letters were commonly issued to those who were participants in an inquiry where there was potential criticism that might be made of their conduct. These letters came to be known was “Salmon letters”.

In his subsequent report in to matters arising from the Matrix-Churchill affair, Lord Scott criticised aspects of the Salmon Principles as being more relevant to adversarial processes than an inquisitorial procedure. However, he took the process of warning those concerned of possible criticism (so they would have an opportunity to comment) further than the Salmon letter; rather, he copied adverse passages from his draft report to those concerned, so they had an opportunity to respond and seek to change his mind. This process is known as “Maxwellisation” and derives from practice in investigations under the Companies Act.

Both processes represent aspects of fairness and may be necessary, depending on the circumstances, for an inquiry conducted today.

For inquiries conducted under the Inquiries Act 2005, the Salmon letter procedure has been codified in to a process of “warning letters” (see section 13 of the Act). This provides that the chairman may not include any explicit or significant criticism of a person in a report unless he has sent a warning letter to a person who:

  • (a) He considers 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 any report or interim report.

Section 14 of the Act creates a statutory duty of confidence between the recipient of such a letter, the inquiry team and the recipient’s legal representative. The duty persists until such time as the inquiry’s report is published or the chairman waives the duty.

The contents of warning letters under the Act are set out in section 15. They must:

  • (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
  • (c) refer to any evidence which supports those facts.
    It has yet to be seen whether the statutory process of warning letters will help speed up inquiries that would previously have followed a Maxwellisation process by dispensing with it, or whether a chairman will consider that fairness requires a “Maxwell” process as well as warning letters under section 13 of the Act

12. Defamation and qualified privilege

The law provides that where a statement is made by one individual about another which is false and damages that person’s reputation, that person may commence proceedings for damages on grounds of defamation.

Those conducting inquiries, and those giving evidence in such proceedings are as susceptible to an action for libel (in respect of written statements) or slander (oral statements) as anyone else.

However, where “qualified privilege” attaches to an inquiry it serves to protect the statement-maker where they make a false and disparaging statement in the course of the inquiry providing the statement is made in good faith.  This is not the case, though, where the statement-maker is motivated by malice.

For inquiries conducted under the Inquiries Act 2005, section 37 codifies the previous common law understanding of the qualified privilege defence to defamation proceedings.  Section 37(3) provides as follows:

  • 37(3) for the purposes of the law of defamation, the same privilege attaches to
  • (a) Any statement made in or for the purposes of proceedings before an inquiry (including the report and any interim report of the inquiry)
  • (b) Reports of proceedings before an inquiry

As would be the case if those proceedings were proceedings before a court in the relevant part of the United Kingdom.

13. Data protection

Those conducting inquiries will wish to reach an early determination on whether or not they are required to register as a “data controller” for the purposes of the Data Protection Act 1998 (“the 1998 Act”).

Under section 2 of the 1998 Act, a data controller is defined as a person who (either alone or jointly or in common with other persons) determines the purposes for which and the manner in which any personal data are or are to be processed.

It is unlawful for personal data to be processed if the relevant data controller has not registered with the Information Commissioner’s office (section 17 of the 1998 Act); and any data controller who processes data without registration is liable to criminal conviction of an offence under section 21 of the 1998 Act.

It is easy to register with the Information Commissioner’s office and notification forms are available by post, by telephone (01625 545 740) or online. There is a fee of £35.

The key question for the inquiry team to determine is whether they simply process information and data on behalf of their commissioning body – in which case they do not “control” the data and do not need to register – or whether they truly determine the manner and purposes for which data is processed. Answering this question is likely to require consideration of the sources of information the inquiry is going to consider, whether it constitutes “data” or “sensitive personal data” as defined in the 1998 Act and the degree to which the inquiry is independent of its commissioning body.

The definition of the terms “data”, “personal data” and “sensitive personal data” are complex and outside the scope of this practice note. Detailed guidance is available at [PLC ref] and from the Information Commissioner’s office.

Whether they are a “data controller” or “data processor”, the inquiry team will need to give careful consideration to redaction of personal and sensitive information (for example before making  disclosure of documents), to comply with the data protection principles contained in Schedule 1 to the Data Protection Act 1998. Care will often, for example, need to be taken to remove home address details, private telephone numbers and medical information from such documents before making them available to those affected by the inquiry.

Similar careful consideration needs to be given to publication of personal information in inquiry reports, as the following case study demonstrates:

Case Study

R (on the application of Stone) v South East Coast Strategic Health Authority and others [1006] EWHC 1668 (Admin)

The Claimant was convicted of two counts of murder and one of attempted murder. His case had received extensive media coverage and some erroneous reporting because he had a history of mental health problems and psychiatric care. Following his conviction, an inquiry was established by the local health authority to examine his care, treatment and supervision prior to his commission of these crimes. While he had cooperated with the inquiry and consented to the publication of its report to health professionals, the Claimant objected to it being made public.

Davis J held that the publication of a report which made reference to Mr Stone’s medical conditions and treatment brought in to play consideration of whether his rights under Article 8 ECHR. In the circumstances of the case, he decided that any interference with these rights was not unlawful. Careful consideration had been given to whether it was possible to redact the report to remove such private information, but Davis J held that “a redacted report of the kind proposed cannot and will not work. it I not practicable to publish a report without disclosing details of Mr Stone’s private medical information”.

Mr Stone also objected to publication of the report on grounds of breach of his rights under the Data Protection Act 1998 and it was admitted that the decision to publish involved processing sensitive personal data. Davis J held, however, that such processing was justified under paragraphs 7 (necessary for the exercise of functions conferred by or under any enactment) and 8 (necessary for medical purposes undertaken by a health professional) of Schedule 3 to the 1998 Act.

14. Disclosure

The person leading an inquiry will need to consider whether it is necessary for them to disclose the information and documentation they consider relevant to those affected by their work.  Timely disclosure of relevant documentation is often an aspect of a fair procedure, for example where a person is to be interviewed or give evidence to the inquiry or where he or she has been asked to make representations to it.

In some cases, where the inquiry decides that fairness requires disclosure of relevant documentation to be made, this requirement can be fulfilled by making the documents in question open to inspection at a certain time and place. Provided the person concerned has been given sufficient notice of their right to inspect the documents, fairness is likely to be complied with, even if the person does not in fact attend to see the documents.

In other situations, a requirement to disclose documents will entail copying the documents to the parties concerned, by hard copy or electronically. In substantial inquiries with voluminous documentation, this can represent a significant task and under section 18 of the Inquiries Act the chairman must take such steps as he considers reasonable to allow the public to view documents provided to the inquiry panel.

However disclosure is performed, it is helpful for the inquiry to maintain an accurate record of what documentation has been made available to whom and on what date, so that any subsequent queries regarding the fairness of proceedings in this respect may be easily checked and answered.

Much of the documentary material considered by an inquiry will be confidential and sensitive. If fairness requires such documentation to be disclosed, those leading the inquiry should consider whether to impose terms about the way in which such information can be seen and restricting its wider dissemination. If they choose to extract undertakings as to confidentiality, early thought should be given to whether and if so to what extent any such undertakings can be enforced.

15. Communicating the findings of an inquiry

The starting point for communicating the findings of any inquiry is a clear, concise, jargon-free written report.  No matter how careful the inquiry process, a wordy, badly-drafted report at its conclusion can serve to obscure rather than reveal the facts. It can also lead to misunderstanding and mis-reporting of the inquiry’s conclusions.

The content of the report will depend on the nature of the case and inquiry, but typically will include:

  • introduction
  • executive summary
  • terms of reference
  • methodology: approach and structure of the investigation
  • background and chronology of events
  • findings
  • conclusions
  • recommendations

In addition to circulating the report to internal stakeholders (such as board members, staff and managers), face-to-face presentations are a useful way of disseminating the key findings quickly and starting the process of change set out in the recommendations. 

The report will also need to be sent to external stakeholders, such as those with a personal interest in the case (perpetrators and the victims and/or their families, partner organisations, commissioners, etc). When communicating with victims and their families or with the perpetrators, it is advisable for a member of the investigative team to meet with them to go through the report and its findings in person and answer any questions they may have. 

Unless there is a good reason not to, most reports will need to be put into the wider public domain (normally timed to ensure internal and external stakeholders have been informed of the findings first).

There are several ways of doing this depending on the likely level of media interest.

For high-profile inquiries that are likely to attract considerable media interest, a press conference is the best way of highlighting key messages and containing coverage within a 24-hour period. Invited journalists are normally asked to attend up to two hours before the press conference starts to give them a chance to read the report.

Briefing a handful of selected journalists on the report - or even breaking the story as an exclusive to a single media outlet - is a lower key option and works well for inquiries that are likely to attract moderate levels of media attention.

For inquiries likely to attract little media attention, it is normally sufficient to submit the report to the board(s) of the organisation(s) involved, make the full report available on the appropriate website(s) and issue a press release to those journalists likely to be interested in the story setting out the key messages. Where no media interest is likely, submitting the report to the board and putting it on the website should suffice.

Section 25 of the Inquiries Act imposes a duty on the relevant minister or chairman to publish the inquiry report.

For further information, please contact Martin Smith.


In this practice note we refer both to investigations and more formal inquiries as “inquiries” apart from where the context demands otherwise, investigations are generally smaller pieces of investigative work, while inquiry are usually larger-scale, formal investigations commissioned under the Inquiries Act 2005.  Both investigations and inquiries are inquisitorial, not adversarial, in nature.