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, which are the most common, are usually established under the Inquiries Act 2005  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. Across the UK, since 2005, 63 inquiries have been launched, compared with 41 in the 20 years prior.

Inquiries are also taking longer to complete which means there are more inquiries ongoing at the same time. Since 1997 there have never been fewer than five public inquiries running at any one time, and as of January 2026 there were 27 inquiries ongoing or announced – the most ever at one time. This includes 22 statutory inquiries and 5 non-statutory inquiries, there are also other types of investigation established by the government such as reviews. 

 Who leads a public inquiry?

Statutory public inquiries are established the government, the UK, Scottish, Welsh and Northern Ireland government have the power to establish such an inquiry. Non-statutory inquiries can be established by other bodies although it tends to be the government.

Although established by the 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.1 The chair is chosen by the minister who initiates the inquiry, with 64% of inquiries launched since 1990 chaired by a judge or former judge. Of the 25 ongoing inquiries with an appointed chair, only two are chaired by someone who is not a current or former judge or lawyer – Rt Rev Dr Pete Wilcox chair of the Orgreave inquiry and Baroness Longfield chair of the grooming gangs inquiry.  Individuals from non-legal background have chaired public inquiries (scientists, social workers, doctors, engineers). For example Kate Eves who has an extensive background in research within custodial environments who chaired the Brook House Inquiry into the mistreatment of detained individuals at an Immigration Removal Centre, and Professor Alexis Jay chair of the Independent Inquiry into Child Sexual Abuse who has an extensive background in social work inspection and previous inquiries into child sexual abuse. Chairs with non legal backgrounds 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. Since 2005 only 13 inquiries (22%) have been 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. ⁴ https://www.gov.uk/government/news/government-strengthens-post-office-horizon-it-inquiry-with-statutory-powers

Provisions included in the Public Office (Accountability) Bill, known as the Hillsborough Law, include a duty of candour and an ancillary duty to assist which extends to non-statutory inquiries established by a government minister. If this bill passes, it would place a duty, backed by possible criminal sanctions on the government, other public bodies and officials to assist with inquiries. This does not however extend to other individuals or organisations.  

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. On average statutory inquiries have taken twice as long as non-statutory inquiries 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. An NAO 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.