For the first time, the Court of Appeal has considered the legal implications of biodiversity requirements introduced in 2005 by the government under a new Planning Policy Statement.
In R on the Application of Buglife v Thurrock Thames Gateway Development Corporation (Court of Appeal (Civil Division)  EWCA Civ 29 28 January 2009) the court rejects a detailed legalistic interpretation of the circular in favour of a more generalised approach. The decision underlines the courts’ reluctance to overrule the professional judgment of statutory conservation bodies consulted on planning applications.
The case concerned the site of a former power station in Thurrock. In 2006, a developer submitted a planning application for developing it as a major distribution depot for Royal Mail. The application was granted by the local planning authority, the Thurrock Thames Gateway Development Corporation, which had been established in 2003 to regenerate the Thames Gateway area.
The site proposed for development was said to be one of the most important areas in Britain for rare or endangered invertebrates, including three key species listed in the UK Biodiversity Action Plan. Because of the impact of the proposed development, the statutory consultee, Natural England, objected at first to the application. But after lengthy negotiations over mitigation measures, including the development of new ecological areas, it was satisfied that the scheme should go ahead provided planning conditions were imposed to ensure development was phased to assist the rehabilitation process. Such conditions were included in the permission.
Buglife, the national Invertebrate Conservation Trust, challenged the decision’s legality. Its main argument concerned the provisions of Planning Policy Statement 9 (PPS9) entitled Biological and Geological Conservation. This was issued by the Office of the Deputy Prime Minister in 2005 and as part of the government’s 2002 Biodiversity Strategy, Working with the grain of nature, and remains in force. Under section 40 of the Natural Environment and Rural Communities Act 2006, public authorities must have regard for biodiversity conservation when carrying out their functions, provided this is consistent with their functions.
Paragraph 1(vi) of PPS9 stated that when granting planning permission that would result in significant harm to biodiversity and geological conservation interests, "local authorities will need to be satisfied that the development cannot be reasonably located on any alternative sites that would result in less or no harm. In the absence of any such alternatives, local planning authorities should ensure that before planning permission is granted, adequate mitigation measures are put in place... if significant harm cannot be prevented, adequately mitigated against, or compensated for, then planning permission should be refused."
Buglife argued that the planning authority had not properly come to grips with the requirements of PPS9. First, it had failed to give proper consideration to alternative sites. An environmental statement had been prepared which stated that Royal Mail as the site’s prospective user had carried out an extensive search for sites and concluded Thurrock was the most suitable.
The requirements concerning alternative sites in paragraph 1(vi) of PPS9 were triggered by the prospect of significant harm. A critical difference in the parties’ approaches was the extent to which one was entitled to take into account proposed mitigation measures in determining significance or not.
Buglife pointed to decisions concerning the need for environmental assessment where similar arguments had been raised, notably the Bellway decision of the Court of Appeal (ENDS Report 339, pp 55-56 ). In those cases, the courts tended to rule that unless the mitigation measures are minor or easily achievable, planning authorities should ignore proposed remediation when considering whether a development has significant environmental effect.
But Lord Justice Pill questioned the analogy. Here, the issue is not whether an environmental assessment is needed, but "whether, and if so to what extent, remedial measures may be taken into account when reaching a decision on harm to species or their habitats". He concluded, as had the High Court (ENDS Report 399, pp 49-50 ), that given the evidence, the authority was entitled to consider the proposed mitigation and also to conclude the harm was not significant. The question of alternative sites never therefore came into play.
Buglife went on to note that paragraph 16 of PPS9 stated that where harm to species or habitats would occur, local authorities should refuse planning permission "unless the need for, or the benefits of, the development clearly outweigh the harm". Here, it argued the authority had simply failed to apply the test. Again, Lord Justice Pill, giving judgment for the court, felt that overall the planning authority had adopted a correct approach and was entitled to give significant weight to the views of Natural England, "the expert statutory consultees".
The final main challenge concerned the phasing plan, proposed by Natural England and required as a condition of the planning permission. Buglife argued that in the absence of any details concerning the plan, it was impossible to carry out a proper environmental assessment, including public consultation.
The court accepted there will be cases where permission cannot be granted without full mitigation proposals or a pre-determined phasing plan. But whether this is legally necessary or not will depend on the case. Here, the court felt the authority did not need a "complete blue-print" in advance, particularly as Natural England acknowledged that the developers’ proposals were sufficient to meet their concerns: "What is in the event appropriate by way of phasing will depend on the detailed development involved and close monitoring of it in relation to the emerging effect on the environment, including the invertebrates."
The Court of Appeal therefore agreed with the High Court’s decision to uphold the planning permission’s validity. The Court of Appeal’s analysis is less rigorous than the High Court’s and, given that this seems to be the first time such biodiversity policy issues have been raised before it, misses the chance to consider in detail some of the legal issues raised. In the High Court, for example, Mr Justice Mitting had noted a possible conflict between the statutory duties of the development corporation to rehabilitate land in its area and the biodiversity requirements of PPS9.
Rather than provide definitive guidance, the Court of Appeal is concerned with the case’s particular facts and an overall assessment of the planning authority’s approach. It accepts the authority never analysed the circular line by line, but warns against approaching a circular’s construction as one might a statute.
The case is clearly a warning to NGOs and others wishing to challenge decisions to be wary of adopting an over-legalistic approach to the construction of policy and other official documents. As Lord Justice Pill concluded: "In analysing this planning decision, consideration of the larger picture, the main issues, should not be defeated by over attention to detail, with the risk of thereby losing, in common parlance, the wood for the trees."
Richard Macrory is professor of environmental law, University College London