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Heather practises primarily in planning and compulsory purchase, environmental and EU law.

Planning and compulsory purchase

Heather is listed as one of the top rated planning juniors and as one of the top ten planning juniors under 35 in the Planning Law Survey 2018. She is a member of the Attorney General’s C Panel of Counsel and of the Welsh Government’s B Panel of Junior Counsel. She is also an Assistant Editor of the Encyclopedia of Planning Law and Practice, with a focus on heritage matters.

Her experience includes the following:

Court work

  • Acting for the successful respondents both at first instance and in the Court of Appeal in DLA Delivery Ltd v Baroness Cumberlege of Newick [2018] EWCA Civ 1305. The High Court decision was one of Planning magazine’s ten “need to know” court rulings for 2017.
  • Appearing for the successful local planning authority in Oldham MBC v Tanna [2017] 1 WLR 1970, in which the Court of Appeal considered the proper interpretation of the service provisions in the Town and Country Planning Act 1990, in the context of proceedings in respect of a s.215 notice.
  • Appearing at first instance and before the Court of Appeal for an affordable housing developer in a statutory challenge to the grant of planning permission for a rural exception site.
  • Acting for the first interested party, a telecommunications operator, in R (o.a.o. Mawbey) v Lewisham LBC [2018] EWHC 263 (Admin), a decision on the meaning of the word “mast” as used in Part 16 of the 2015 GPDO.
  • Successfully defending the judicial review claim in Smech Properties Limited v Runnymede Borough Council [2016] JPL 677, which raised before the Court of Appeal an important point concerning the High Court’s discretion not to quash a defective grant of planning permission (led by Nathalie Lieven QC and David Forsdick QC).
  • Successfully resisting on behalf of the developer a judicial review challenge to the grant of planning permission for the redevelopment of the former HMS Ganges site at Shotley Gate, Suffolk (led by David Elvin QC).
  • Appearing for nine claimant London local planning authorities in a High Court challenge to the Mayor of London's Revised Early Minor Alterations to the London Plan, on grounds relating to affordable rented housing (led by Nathalie Lieven QC).
  • Regular appearances in the Crown Court and in the Magistrates' Court in planning enforcement proceedings.

Planning inquiries

  • Appearing for the appellant at a forthcoming inquiry in respect of a proposed mixed-use development that includes 1,200 dwellings (junior to Christopher Lockhart-Mummery QC).
  • Acting for the developer at a five week inquiry into the proposed development of up to 2,068 dwellings at the former Wisley Airfield, Surrey, a Green Belt site that is partially previously developed land (led by James Maurici QC).  
  • Appearing for the local planning authority at two inquiries in respect of proposed Sustainable Urban Extensions of 1,000 houses each (led by Timothy Corner QC).
  • Appearing for the appellant at a six day inquiry into a retail-led regeneration scheme (led by Charles Banner).
  • Sole counsel for the successful local planning authority at a four day inquiry that raised heritage and landscape issues.
  • Regular appearances for appellants and local planning authorities in lawful development certificate inquiries and enforcement inquiries.


  • Advising the Department for Transport on airports expansion in the South-east of England and the forthcoming Airports National Policy Statement (counsel team led by James Maurici QC).
  • Advising in respect of the National Policy Statement for new nuclear above 1GW post 2025: siting criteria and process (junior counsel).
  • Advising as sole counsel on the Space Industry Act 2018 (at Bill stage).
  • Appearing for the claimant, a commercial objector, in R (Trago Mills Ltd) v SSCLG [2016] EWHC 1792 (Admin), a High Court challenge relating to a Development Consent Order.
  • Advising on EIA of a biomass plant.
  • Acting as junior counsel for the developer in a successful challenge to the refusal of consent for a wind farm in Powys.
  • Successfully resisting (on behalf of the developer) a judicial review challenge to the grant of planning permission for the Beddington Energy Recovery Facility (led by David Elvin QC).
  • Appearing for Lambeth Borough Council in a claim for judicial review of its decision to grant planning permission for the "Garden Bridge" (led by Nathalie Lieven QC).
  • Advising on a proposed challenge to the Secretary of State’s decision not to "call in" an application for planning permission for development at London Luton Airport.

Compulsory purchase

  • Acting for the acquiring authority at the inquiry into the recently confirmed London Borough of Enfield (Alma Estate Regeneration) CPO 2016 (junior to David Elvin QC).
  • Advising in respect of the Worcestershire Parkway Regional Interchange CPO.
  • Advising on the Worcester Southern Link Road CPO. 


Heather has a particular interest in EU environmental law, having worked on Case C-258/11 Sweetman v Ireland (Article 6 of the Habitats Directive) as a trainee at the Court of Justice of the EU in 2012. Her EU environmental experience includes:

  • Cumberlege v SSCLG [2017] PTSR 1513 (above), which addresses the requirements of reg. 68(3) of the Conservation of Habitats and Species Regulations 2010.
  • Successfully defending (in both the High Court and the Court of Appeal) on behalf of the Homes and Communities Agency a judicial review challenge on Habitats grounds to the grant of planning permission by Forest of Dean District Council for development in Cinderford’s "Northern Quarter" (led by James Maurici QC and Timothy Corner QC).
  • Extensive advisory experience in respect of the EIA, SEA and Air Quality Directives and of the related domestic transposing provisions.
  • Advising the Department of Energy and Climate Change on infraction proceedings proposed by the European Commission (junior to David Blundell).

Other environmental experience includes:

  • Successfully defending King v Environment Agency [2018] EWHC 65 (QB), a claim for damages brought on human rights grounds in relation to flooding (led by Gwion Lewis).
  • Successfully acting for the Environment Agency in High Court challenges relating to the operation of the environmental permitting regime in the waste context.
  • Defending injunctive proceedings on behalf of Natural England.
  • Defending a prosecution pursuant to section 34 of the Environmental Protection Act 1990.
  • Advising on the Climate Change Act 2008.
  • Advising a local authority on how to approach long-term flood risk.
  • Regularly advising in respect of the Aarhus Convention fixed costs regime.


Heather spent 10 months working as a trainee in the EU institutions during 2011-2012, first for the Legal Service of the European Commission (Competition law) and subsequently at the Court of Justice of the EU (Cabinet of Advocate-General Sharpston).

In addition to EU environmental law, she has particular experience of both EU State aid law and EU public procurement law. This includes:

  • Acting for the claimant in a judicial review challenge to the local planning authority’s interpretation of State aid provisions in the Community Infrastructure Levy (“CIL”) Regulations 2010 (led by James Maurici QC).
  • Appearing for the claimant in the High Court in R (o.a.o. Faraday Development Ltd) v West Berkshire Council [2016] EWHC 2166 (Admin), a public procurement, best value and State aid challenge to a £125 million development agreement (led by Charles Banner).   
  • Advising a contracting authority on the procurement of community transport services.
  • Co-author (with James Maurici QC) of an article in the Journal of Planning and Environment Law on "State aid in planning and compulsory purchase order cases" (JPL 2015, 6, 621-643).

Other EU law experience includes acting pro bono in several sets of proceedings before the First-tier Tribunal (Social Security and Child Support) and the Upper Tribunal concerning EU residence rights, instructed by the AIRE Centre on behalf of the claimants. 

Public Law

Heather has a long-standing interest in public law, having previously given tuitions in Administrative Law to students at the University of Oxford, taught Constitutional and Administrative Law at Birkbeck and written an MPhil thesis on the Human Rights Act 1998.

Other Interests

Heather speaks fluent French and is learning Welsh. Away from Chambers she enjoys playing the piano and the viola, taking dance classes and going to the theatre.