The challenge has been brought by five Claimants - four London borough councils (Hillingdon, Bexley, Bromley and Harrow) and Surrey county council. It concerns the controversial decision taken by the Mayor in November 2022 to expand the ULEZ so as to encompass the whole of outer London. The Mayor and Transport for London are seeking to implement the expansion on 29 August 2023, which will require any non-compliant vehicle to pay a £12.50 daily charge to enter the zone.

The Claimants were granted permission on the papers by Sir Ross Cranston (sitting as a High Court Judge) for two grounds on 12 April 2023 (see further here ). Following an oral renewal hearing, Ellenbogen J granted permission for further grounds on 26 May 2023. 

In summary, the grounds of challenge are:

1. That the introduction of the ULEZ expansion through a variation order to an existing charging order (as opposed to a new charging order) was ultra vires and failed to comply with the requirements of Schedule 23 of the Greater London Authority Act 1999 and/or frustrated the statutory purpose of that legislation.
2. That the consultation process was unfair and unlawful regarding the expected reference case compliance rates for outer London, predicted at 91% for private cars by 29 August 2023 without the ULEZ expansion:

a.    The information provided on this estimated compliance rate was unintelligible;

3. Further, and in any event, key information relating to camera data – necessary to enable consultees to understand the accuracy of the estimated compliance rate and respond intelligently – was not disclosed. In relation to the scrappage scheme mitigation:

a.    The Mayor failed to take into account a material consideration/acted irrationally by failing to consider the potential for affected non-Londoners to be included in the new scrappage scheme mitigation and the inconsistency of the proposed approach not to extend the scheme. When the ULEZ was previously expanded from central to inner London, a scrappage scheme had applied to all Londoners, effectively applying a “buffer zone” of mitigation to those who lived outside the expanded ULEZ zone but were nonetheless affected by it. Nor did he give adequate reasons for his decision. 
b.    The Mayor had insufficient details on the proposed scrappage scheme to rationally rely on it as mitigation.
c.    The consultation was unfair and unlawful as it failed to provide sufficient details on the proposed scrappage scheme to enable consultees to make intelligent, proper and effective responses to the principal mitigation being proposed and relied on.

The case has attracted considerable coverage in the press, for example see:
BBC - 4 July 2023
BBC - 6 July 2023
BBC - 9 July 2023
Evening Standard - 4 July 2023
Evening Standard - 9 July 2023
Evening Standard - 4 July 2023
The Guardian - 4 July 2023
The Times (paywall)
Reuters - 4 July 2023
Bloomberg - 4 July 2023
LBC - 4 July 2023

See also on the permission decision on 26 May:
BBC
Local Government Lawyer
Ends Report (paywall)

A decision is awaited, but is expected within the next month.

Craig Howell Williams KC and Merrow Golden are representing the Claimants.