Public inquiries

What is a public inquiry?

Public inquiries are official investigations, established by a UK or devolved government minister, but conducted by an independent body, to examine matters of “public concern” about a particular event or set of events.

Inquiries have addressed topics such as transport accidents, fires, the mismanagement of pension funds, self-inflicted deaths in custody, outbreaks of disease, and decision making that has led the UK to go to war.

There are two main types of public inquiry – statutory and non-statutory. Statutory inquiries are usually established under the Inquiries Act 2005 ⁸ Inquiries Act 2005, www.legislation.gov.uk/ukpga/2005/12/contents  which grants special powers to compel testimony and the release of other forms of evidence.

What is the purpose of a public inquiry? 

The precise role of a public inquiry may differ significantly depending on the topic and terms of reference. For example, not all inquiries will be required to make recommendations.

According to the Ministry of Justice, the government considers “preventing recurrence” to be the primary purpose of public inquiries. Jason Beer KC, the UK’s leading authority on public inquiries, argues that public inquiries address three key questions:

1. What happened?
2. Why did it happen and who is to blame?
3. What can be done to prevent this happening again?

To answer these three questions, inquiries start by collecting evidence, analysing documents and examining witness testimonies. They will often draw on experts, policy professionals, and victims and survivors’ testimony to help them form recommendations. Between 1990 and 2024, 54 inquiries made 3,175 recommendations.

The remit of a public inquiry is set out in the terms of reference (TORs). These are specific instructions outlining the questions that the inquiry should address, the types of information and feedback that the government wants, and often an indicative timeline for when the inquiry should issue its report. Increasingly, inquiry chairs consult on the terms of reference with individuals and groups affected by the issue. Partly because of this, TORs have grown longer and more detailed.

How common are public inquiries?

The number of inquiries convened has risen over recent years, alongside a longer-term shift away from other forms of investigation such as royal commissions.

Since 1997 there have never been fewer than five public inquiries running at any one time, and as of February 2025 there are 20 inquiries ongoing or announced – the most ever at one time.

Between 1990 and 2025, 88 public inquiries have been launched – compared with only 19 in the 30 years prior to this. 

Who leads a public inquiry?

Although initiated and funded by government, public inquiries are run independently. Ministers have the power to remove a chair or terminate the whole process – but no minister has ever exercised this power.

Each inquiry involves a chair or chairs (responsible for running the inquiry and drafting the final report), a counsel to the inquiry, an inquiry secretary, a solicitor to the inquiry, secretariat and core participants. The chair is chosen by the minister who initiates the inquiry, with 68% of inquiries launched since 1990 chaired by a judge or former judge. Of the 18 ongoing inquiries with an appointed chair, 13 are chaired by a current or former judge and three by a barrister. 

Individuals from non-legal background have chaired public inquiries (scientists, social workers, doctors, engineers). These tend to be drawn from professions that enjoy far higher levels of trust amongst the UK public than the government ministers who establish inquiries.

Inquiry chairs tend to lack diversity – typically being older, white and male. Between 1990 and 2024 only 15% of inquiries (13) were led by female chairs. 

What is the legal basis for public inquiries?

Most inquiries are now convened using the Inquiries Act 2005, which provides a uniform set of powers and rules for how an inquiry operates. The Inquiry Rules 2006 set out additional detail regarding evidence and procedure. Before the Inquiries Act 2005, at least 10 different pieces of legislation had been used to provide a statutory basis for inquiries.

Inquiries can also be convened on a non-statutory basis. These inquiries lack subpoena powers and ability to take evidence under oath that statutory inquiries have. They are regarded as less adversarial and enjoy more freedom to define how they operate. Non statutory inquiries can be converted to a statutory inquiry, as was the case with the Post Office Horizon IT Inquiry. ¹⁰ Department for Business, Energy and Industrial Strategy, The Rt Hon Kwasi Kwarteng, Paul Scully and The Rt Hon Boris Johnson, Government strengthens Post Office Horizon IT inquiry with statutory powers, GOV.UK, press release, 19 May 2021, www.gov.uk/government/news/government-strengthens-post-office-horizon-it-inquiry-with-statutory-powers

How long do public inquiries take?

Public inquiries often take a long time. In contrast to inquests, which must make a formal report offering an explanation to the chief coroner if they take longer than a year, inquiries have no set time frame.

Public inquiries have varied greatly in duration, although on average the completed inquiries launched since 1990 have taken just over three years to report back. The shortest inquiry was the Hammond Inquiry into ministerial conduct relating to the Hinduja affair; this took only 45 days. The longest was the inquiry into Hyponatraemia-related deaths; this took 13 years and three months to complete.

Why do some public inquiries take so long?

The announcement of an inquiry is followed by the appointment of a chair, the agreement of terms of reference, and set up before the opening session. This process can last for some time. Inquiries dealing with very complex issues, or covering especially technical legal debates will often take longer at this stage. The still ongoing inquiry into undercover policing took five years from being announced in 2015 to holding its opening session. 

A third of time taken by the Edinburgh Tram and the Litvinenko inquiries was spent in this setting up stage, and more time was spent convening than actually holding the inquiry into the death of Jermaine Baker.

Inquires must review thousands of documents and take witness testimony, while individuals who may be subject to criticism in an inquiry’s report must be sent warning letters. ‘Maxwellisation’ as it is known, can slow down the process as individuals have the right to respond to the criticisms before publication. If they do the inquiry will need to review the response. Recipients of warning letters can take considerable time to review the allegations and may request extensions while they consult legal advisors and draft detailed responses. Major inquiries often involve numerous individuals and organisations who must be contacted which can significantly prolong the process.

Some inquiries have also been delayed due to staff turnover. Few have struggled as much as the Independent Inquiry into Child Sexual Abuse, which by the end of 2017 was on its fourth different chair. Other inquiries have been delayed after losing chairs to sickness and death.

Public inquiries are commonly delayed when criminal investigations by the police take place at the same time. Inquiries cannot determine criminal or civil guilt – a function reserved for the courts. However, criminal investigations and trials running alongside inquiries will often involve many of the same witnesses. Some may be unable to give testimony to an inquiry because in doing so they risk incriminating themselves.

How much do public inquiries cost?

Inquiries are notoriously expensive. The Bloody Sunday Inquiry cost £272.5m (in 2024 prices).

Between 1990 and 2024 the UK and devolved nations spent at least £1.5bn on completed public inquiries (2024 prices). The actual cost will have been higher, since not all inquiries publish their costs and others are ongoing. 

A significant component of the costs of an inquiry are legal staff. A National Audit Office report of a sample of public inquiries found that legal staff accounted for an average of 36% of the total costs. Other significant costs include running costs, consultancy and other staffing.

What recommendations have been made to improve the running of inquiries?

Public inquiry recommendations often face significant implementation challenges due to cost constraints, feasibility issues, and resistance from stakeholders. Weak enforcement mechanisms and shifting government priorities mean that many proposals are delayed, watered down, or ignored. 

A House of Lords inquiry to review the Inquiries Act 2005, held in 2024, made multiple recommendations for improving the effectiveness of public inquiries, including monitoring and implementation of recommendations.

Several previous inquiries have themselves picked up on the lack of implementation of previous recommendations. The Thirlwall Inquiry, investigating the circumstances surrounding the actions of former nurse Lucy Letby, conducted a review of past inquiry recommendations into healthcare issues and found that many had not been acted on. ¹² The Thirlwall Inquiry, Review of Implementation of Recommendations from Previous Inquiries into Healthcare Issues prepared by the Thirlwall Inquiry Legal Team, 15 May 2024, https://thirlwall.public-inquiry.uk/2024/05/17/review-of-previous-recommendations-published/?d102_cookies_enabled=all

Several inquiries have also made recommendations for improving follow-up in their own reports:

The Grenfell Inquiry Phase 2 report recommended:

• A publicly accessible record of recommendations made by select committees, coroners and public inquiries which the government must use to track the progress of implementation, or otherwise explain why it has failed to implement recommendations.
• Scrutiny of government actions should be a matter for parliament, and that the government should report to parliament on its progress annually.

Relatedly, the Infected Blood Inquiry recommended:

“Because the findings of public inquiries often sit across several select committees, the Public Administration and Constitutional Affairs Committee (PACAC) is best placed to view the responses ‘as a whole’ and should review progress on responding to and/or implementing recommendations.”

PACAC held its own inquiry in 2017 into the lessons learned from the long-running Chilcot Inquiry into the nation’s role in the Iraq War, it recommended:

• Parliament should be given a greater role in establishing the terms of reference of an inquiry, potentially through an ad hoc select committee, and in determining whether the inquiry should be given a statutory footing.
• MPs should be given a vote on an amendable motion before terms of reference are formally set, indicating at the same time both a timescale and budget for the inquiry.