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How much do public inquiries cost and how long do they last?

A public inquiry is an investigation set up by a government minister, which can be either statutory or non-statutory. Most inquiries are statutory and governed by the Inquiries Act 2005, meaning they have more powers than non-statutory inquiries and operate by more rigid rules.

There is wide variation in how much public inquiries cost and how long they last for. In 2026 prices, the median statutory inquiry costs £6,600 per day. However, several inquiries had a substantially higher cost per day: in 2026 prices, the Independent Inquiry into Child Sexual Abuse cost £74,800 per day, the Grenfell Tower Inquiry cost £67,000 per day and the Infected Blood Inquiry cost £52,500 per day.

More information about how inquiries operate can be found in the Commons Library research briefing on Public inquiries. Key facts about each inquiry can be found in the Commons Library data dashboard on Public inquiries established under the Inquiries Act 2005.

Cost

How much do public inquiries cost?

The median final cost of a statutory inquiry is £9.1 million (or £11.5 million in 2026 prices).

The cost of an inquiry depends partly on how long an inquiry lasts, and partly on how narrow or broad the inquiry’s terms of reference are. An inquiry set up to investigate an individual death, for example, is likely to cost much less than an inquiry set up to investigate an issue of public concern that affects the whole country.

Since the Inquiries Act 2005 was passed, the lowest final cost of a statutory inquiry was £0.4 million (or £0.6 million in 2026 prices) for the Inquiry into the death of Bernard (Sonny) Lodge, who died by suicide while in prison in 1997. The highest final cost of a statutory inquiry was £194.6 million (or £220.0 million in 2026 prices) for the Independent Inquiry into Child Sexual Abuse.

The most expensive statutory inquiry to date is still ongoing: the UK Covid-19 Inquiry has cost £219.8 million, as of 30 June 2026.

How are the costs of an inquiry managed?

The costs of an inquiry include the pay and expenses of the inquiry chair (and inquiry panel, if any), staffing costs for the inquiry secretariat, legal costs and expenses for witnesses, as well as administrative expenses such as office space, IT and telecommunications.

Under section 39 of the Inquiries Act 2005, an inquiry’s costs are paid by the UK Government department and/or devolved administration that sponsors the inquiry. The sponsoring minister must publish an inquiry’s total costs “within a reasonable time after the end of the inquiry”.

Inquiries generally publish their costs on their websites on a quarterly or annual basis, though this is not a requirement under the act and some inquiries publish their costs more promptly than others.

Duration

How long do public inquiries last?

The median duration of a statutory inquiry is three and a half years (1,313 days).

The shortest statutory inquiry under the Inquiries Act 2005 was the Inquiry into the death of Bernard (Sonny) Lodge, which lasted less than a year (295 days). The longest was the Edinburgh Tram Inquiry, which looked at the costs and delays in implementing Edinburgh’s tram system and lasted over eight years (3,238 days). In the final report of the Edinburgh Tram Inquiry, the chair attributed the long length of the inquiry to administrative issues with IT, office space and staffing, as well as difficulties the inquiry faced obtaining documents from witnesses.

The longest statutory inquiry to date is still ongoing: the Robert Hamill Inquiry, into the death of a man in Northern Ireland in 1997, was established on 16 November 2004 and has still not published its final report. The report was completed in 2011 but was not submitted to the minister or published at the time, due to the risk of interfering with criminal proceedings. The Secretary of State for Northern Ireland stated in December 2025 that legal proceedings had concluded and that steps were being taken to publish the report.

What are the stages of a public inquiry?

Under section 5 of the Inquiries Act 2005, an inquiry is established on the setting-up day decided by the minister. Inquiries are sometimes established on the same day that they are announced, but there is normally a gap while the minister selects a chair and decides on the terms of reference.

Once an inquiry is established, it can collect documentary evidence, hold hearings and write one or more inquiry reports.

Under section 14 of the Inquiries Act 2005, an inquiry is formally closed on the date on which the chair informs the minister that the inquiry has fulfilled its terms of reference. This cannot happen until the chair has submitted their final report to the minister. An inquiry can instead be formally closed by the minister before a report is published, although this power is not commonly used.

Inquiries are often closed at the same time as, or shortly after, their final report is published. However, in some cases there has been a significant gap before an inquiry is formally closed. For example, the Leveson Inquiry into press standards published its part 1 report in 2012, with a part 2 set to follow once criminal investigations had concluded. However, part 2 was never held and the minister formally closed the inquiry in 2018.

For a small number of inquiries, it has not been possible to find confirmation of the official closing date. In these cases, the date of report publication has been treated as the closing date.

Do ministers set budgets and timelines for public inquiries?

Ministers have not typically set a maximum budget for an inquiry, though this may be changing. When the Independent Inquiry into Grooming Gangs was established in April 2026, the Home Secretary mandated in the terms of reference that the inquiry must last for no more than three years and operate within a budget of £65 million.

While ministers have occasionally used the terms of reference to set a deadline by which an inquiry should produce its final report, no statutory inquiry has ever published its final report by this deadline: the Clostridium Difficile in Northern Trust Hospitals Inquiry missed its reporting deadline by just under a year (355 days), the Vale of Leven Hospital Inquiry and the Mid Staffordshire NHS Foundation Trust Inquiry missed their deadlines by between one and two years (542 and 678 days respectively), and the Brook House Inquiry missed its deadline by over two and a half years (1,048 days).