They are the principal authorities in Greater London and have responsibilities including education, housing, planning, highways, social services, libraries, recreation, waste, environmental health and revenue collection.

Some of the powers are shared with the Greater London Authority, which also manages passenger transport, police and fire.

[3] Ben-Hassell was a local party official who was working as a project manager for the City of London Corporation.

[6] The subsequent by-election on 7 November 2019 was won by the Labour candidate Caragh Skipper on a reduced majority, while the Liberal Democrats more than doubled their share of the vote.

[8] In November 2020, Croydon council announced its "de facto bankruptcy" by issuing two section 114 notices.

[9] In February 2021, Newman and Hall were suspended from the Labour party after a report was produced into their conduct in the lead-up to the effective bankruptcy of the council.

[10] A Labour councillor for South Norwood, Jane Avis, resigned for personal reasons in March 2021.

A Conservative councillor for Park Hill & Whitgift, Vidhi Mohan, resigned at the same time "due to increasing demands in [his] professional life".

[13] Simon Hall's ward, New Addington North, elected the Labour candidate Kola Agboola.

In February 2021, the Labour councillor and former Conservative MP Andrew Pelling called for Ali to resign unless she could "prove that she asked... questions when she was in Newman's cabinet" about a £37.5 million overspend during the refurbishment of Fairfield Halls.

[15] A campaign group supporting an elected mayor for Croydon called DEMOC started a petition in February 2020, which they submitted to the council in September 2020.

The Labour councillor Sean Fitzsimons defended the choice to hold the referendum in October, saying that the prospective mayor could then be elected alongside the council in May 2022.

[22] Nick Bowes, the chief executive of the Centre for London, wrote that the election would come down to the Labour council mismanaging finances and the national Conservative government's "unpopularity in London", saying that Labour's mayoral candidate, Val Shawcross, would benefit from not being connected to the council's bankruptcy.

All registered electors (British, Irish, Commonwealth and European Union citizens) living in London aged 18 or over were entitled to vote in the election.

[47] [48] The Park Hill and Whitgift by-election was triggered by the resignation of Conservative councillor Jade Appleton.