[2] The OBR examines and reports on the sustainability of the public finances and provides analysis and forecasts on the economy at the time of the UK Government's Budget and Spring Statements.

[9] In the Economic and fiscal outlook, the OBR assesses whether the Government has a greater than 50 per cent probability of hitting these targets under current policy.

Given the uncertainty inherent in all fiscal forecasts, the OBR also tests how robust this judgement is by using historical evidence, sensitivity analysis and alternative scenarios.

During the run-up to the Budget and the Spring Statement, the OBR subjects the Government's draft costings of tax and spending measures to detailed challenge and scrutiny.

[11] In 2022, the OBR was notably not asked for a fiscal forcecast by the short-lived Truss ministry prior to announcement of its' ultimately controversial mini-budget by the then Chancellor of the Exchequer Kwasi Kwarteng which contained a large amount of tax cuts.

The decision of the Truss ministry to ignore the OBR and pursue large tax cuts was and remains widely derided by the political establishment and some figures in the British media.

The mini-budget ultimately triggered the start of a government crisis which saw Truss forced to resign and replaced by Rishi Sunak as Prime Minister after just 49 days in office.

[15] In July 2017, OBR published a review of risks from the economy and financial system, to tax revenues, public spending and the balance sheet, and included a fiscal stress test.

[20] In a Command Paper published with the Wales Bill 2014, the Government requested that the OBR produced forecasts for Welsh devolved taxes.

In March 2014, the Charter for Budget Responsibility was modified to include a new cap on welfare expenditure alongside the Government's fiscal mandate.

As part of this function, the OBR is required to produce a forecast for welfare spending in scope of the cap in its Economic and fiscal outlook.

Robert Chote has discussed the role of the OBR, and the difference that it made after its first three years in existence, in a lecture entitled Britain's fiscal watchdog: a view from the kennel on 9 May 2013.

[29] The objective underpinning its creation was to provide an independent assessment of national public finances before the coalition Government's emergency budget in June 2010, which outlined the size and pace of the fiscal consolidation plan inherited from the outgoing administration.

[26] The role of the Office is to advise whether the declared policy of the Government is likely to meet its targets [30] The OBR was initially chaired by Sir Alan Budd who, along with Geoffrey Dicks and Graham Parker, formed the Budget Responsibility Committee.

[34][35] The Financial Times reported "His departure was expected and Sir Alan had let it be known privately that he had never intended to serve as chairman of the OBR for anything other than a short period.

"[36] Speculation on his successor had included Rachel Lomax, John Gieve, Andrew Dilnot, Robert Chote, Michael Scholar and Ruth Lea.

[3] The OBR has been reviewed a number of times since it was established in 2010: Chote, Nickell and Parker were reappointed for their second terms in September 2015,[43] November 2013[44] and October 2014[45] respectively.

In January 2017, Prof. Sir Charles Bean, former Deputy Governor for Monetary Policy at the Bank of England, replaced Nickell as the economy expert on the BRC.

[47] In January 2022, David Miles, former external member of the Bank of England Monetary Policy Committee and Chief UK Economist at Morgan Stanley, replaced Bean as the economy expert on the BRC.

[49] The following year in June 2018, Bronwyn Curtis OBE joined as a Non-executive member and Audit sub-Committee chair, replacing Lord Terry Burns.

They are: The OBR's Oversight Board ensures that effective arrangements are in place to provide assurance on risk management, governance and internal control.

[58] In a Command Paper published with the Wales Bill 2014, the Government requested that the OBR produce Welsh forecasts alongside each Economic and fiscal outlook.