Covid inquiry: What is it investigating and how will it work?

The public inquiry into the government's handling of the coronavirus pandemic holds its first public hearing on Tuesday 13 June.

The government is challenging its request to see messages sent between former Prime Minister Boris Johnson and colleagues.

Public inquiries respond to "public concern" about events. Although established and funded by governments, they are led by an independent chair.

An inquiry has the power to make people appear as witnesses, and to provide evidence. Inquiries are expected to publish conclusions and may make recommendations.

The Covid inquiry, launched by Boris Johnson in May 2021, is investigating the government's handling of the pandemic. It will cover decision-making in Westminster and the devolved administrations.

It is being chaired by Baroness Heather Hallett, a retired judge and crossbench peer.

She previously led the inquests into the 7 July bombings.

The inquiry has no formal deadline but is due to hold public hearings until 2026.

When it was announced, Boris Johnson said all aspects of the UK's response would be "under the microscope".

The first are:

The next - with hearings in 2024 and 2025 - are:

Public hearings will be held in all four UK nations.

Scotland is also holding a separate inquiry.

Baroness Hallett's team is expected to focus on the biggest and most controversial aspects of the government's response, including:

The inquiry is also expected to consider whether too many restrictions were imposed as the pandemic progressed.

Over the course of 80 days in autumn 2020, England went from the so-called "rule of six" to a tiered system of regulations, then into a national lockdown and then back to tiers.

The inquiry is also expected to consider the government's policy towards schools. These closed to most pupils in March 2020 and then again in January 2021. They only fully reopened after hairdressers and pubs.

Although a full list of witnesses has not been published, senior government ministers and officials are expected to give evidence under oath.

Sir Chris Whitty, the UK government's chief medical adviser during the pandemic, and Sir Patrick Vallance, chief scientific adviser, are likely to appear.

Members of the public have also been invited to share their experiences through the inquiry's Every Story Matters project.

The Covid-19 Bereaved Families for Justice campaign group - which has been critical of the government's handling of the pandemic - has urged the inquiry to ensure these voices are heard.

The inquiry has asked to see unredacted WhatsApp messages between Boris Johnson and 40 people.

They include former No 10 advisor Dominic Cummings, Cabinet Secretary Simon Case and former Chancellor and current Prime Minister Rishi Sunak.

The Cabinet Office launched a legal challenge against the request, arguing the messages are irrelevant. This is thought to be the first time a government has taken legal action against its own public inquiry.

Baroness Hallett said it was her job to decide if material was relevant.

However Mr Johnson said he was "perfectly content" for the inquiry to have WhatsApp messages sent after May 2021. Earlier messages are not available because his mobile phone was involved in a security breach and has not been used since.

Former Health Secretary Matt Hancock also said he was happy to share his messages, although many of these have already been leaked by the journalist Isobel Oakeshott, who helped Mr Hancock write his book, Pandemic Diaries.