Cheshire East

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Seeing through the smog

Pollution 28909383 s 146x219How can local authorities interpret DEFRA’s Clean Air Zone Framework in compliance with the law? Anna Heslop looks at the background and an important legal test.

In May 2017, DEFRA published its Clean Air Zone Framework. This document is intended to guide local authorities who decide to or are required to consider the implementation of Clean Air Zones in England.

The Framework provides information for local authorities on the options for implementation of a Clean Air Zone, but it fails to explicitly mention an important piece of legal context.

When considering what measures to take to tackle poor air quality, decision makers must look for the option which will meet the legal limits for nitrogen dioxide (NO2) in the shortest possible time. Only where it has identified two equally effective options may a decision-maker take into account other factors such as cost.

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In 2010 the formal deadline passed for EU Member States to comply with legal limits for NO2 pollution set under the Ambient Air Quality Directive (Directive 2008/50/EC) to protect human health. Where a breach of the limits takes place after the deadline has passed, Member States are required to prepare an Air Quality Plan which includes measures that make it not just possible, but likely that legal limits will be met in the shortest time possible.

For the purposes of the Directive the UK is split into 43 zones and agglomerations. Seven years on from the deadline, the UK continues to breach legal limits in 37 out of 43 zones.

Since 2011, ClientEarth has been on a lengthy journey through every level of the UK courts, seeking to secure clean air across the UK. In April 2015 the Supreme Court found the Secretary of State to be in breach of the Directive and ordered an updated Air Quality Plan be prepared which should include measures to meet the legal limits in the shortest time possible.

In December 2015 DEFRA published the ordered Air Quality Plan. Unfortunately that plan had a range of problems and in November 2016 the High Court ordered DEFRA to try again. The latest iteration of the Air Quality Plan was published on 27 July this year.

In the 2015 Air Quality Plan, five local authorities had been mandated to implement a Clean Air Zone – an area that polluting vehicles of certain classes would be charged to enter. In the 2017 plan those five cities, together with 23 additional local authorities are required to undertake feasibility studies to determine what measures should be taken in their local area to meet the limits for NO2 in the shortest possible time.

DEFRA’s own evidence indicates that charging vehicles to enter these zones is likely to be the quickest route to compliance, but local authorities are asked to first consider whether there are other equally effective options which don’t involve charging.

Alongside the draft of the Air Quality Plan published in May, DEFRA published a Clean Air Zone Framework for England. This framework sets out the principles for setting up a Clean Air Zone in England.

Unfortunately the Framework does not explicitly describe an important legal test which was set out by the High Court in November 2016 in R (ClientEarth) (No2) V Secretary of State for Environment Food and Rural Affairs [2016] EWHC 2740 (Admin).

On the question of whether a Member State could have regard to cost when considering different measures to tackle air pollution, the Court found (para 50) that “there can be no objection to a Member State having regard to cost when choosing between two equally effective measures….. But I reject any suggestion that the state can have any regard to cost in fixing the target date for compliance or in determining the route by which the compliance can be achieved where one route produces results quicker than another. In those respects the determining consideration has to be the efficacy of the measure in question and not their cost. That, it seems to me, flows inevitably from the requirements in the Article to keep the exceedance period as short as possible”.

In other words, when selecting measures to tackle air quality, the determining factor must be which measure will meet the legal limits in the shortest time. Only where two measures are equally timely and effective can considerations such as cost be taken into account.

Since the responsibility for selecting measures has now been passed to local authorities, they will need to be aware of this important legal test when commissioning or carrying out feasibility studies and in subsequent decision-making.      

Anna Heslop is a clean air lawyer at ClientEarth.

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