No5 Barristers' Chambers

Planning and Environment

Barristers

Jessica Allen is a specialist environmental lawyer who welcomes instructions in all areas of environmental law, including planning, property, public law, environmental torts, and EU/international law. Before coming to the Bar, Jessica held legal and policy roles at WWF, the Environmental Law Foundation, and ClientEarth.

Jessica regularly acts for and advises individuals, community groups, NGOs, landowners, developers, and local and central government in various fora and on a range of environmental law matters including judicial review challenges, planning appeals, restocking notice appeals, abatement notice appeals, and environmental assessments (HRA/EIA). She has appeared in senior courts up to the Court of Appeal.

Recent instructions include:

R (on the application of Smar Holdings Ltd) v Secretary of State for Environment, Food and Rural Affairs [2025] EWCA Civ 1041: Acting for the respondent in an appeal against a successful judicial review of the Secretary of State’s decision to uphold a restocking notice which raised issues including whether the prospect of a planning permission or an emerging development plan allocation was capable of being a material consideration (led by Hugh Richards); Acting for the claimant in a judicial review of a council’s decision to grant planning permission for a 28 hectare aggregate quarry in circumstances where the full range of climate change impacts of the development had not been assessed or taken into account (consented); Acting for the claimant community group in a judicial review of a council’s decision to grant planning permission for a wedding and events venue in circumstances where a supplementary planning document on development in an area of outstanding natural beauty had not been taken into account (consented); Acting for the respondent council in an appeal against an abatement notice relating to a noise nuisance arising from industrial premises on grounds including that there was no nuisance and the notice was defective; APP/C1760/W/24/3354052 Land East of Halterworth Lane, Romsey: Acting for the respondent council at an inquiry into a 270-home residential scheme on greenfield land raising issues of settlement coalescence and landscape harm; and

APP/C3430/W/24/3355879 Land at Orton Hall Farm, Flash Lane: Acting for the appellant developer at a hearing for the erection of a dwelling in the Green Belt raising Green Belt, locational sustainability and landscape issues.

English (Native), French (Advanced)

UKELA (UK Environmental Law Association)

PEBA (Planning and Environmental Bar Association)

ALBA (Constitutional and Administrative Law Bar Association)

Gray’s Inn

Bachelor of Civil Law – Distinction (University of Oxford, 2018)

BA (Hons) Law with French and French Law – First Class (University of Nottingham, 2017)

Diplôme d’Études du Droit de l’Union Européenne (Université Toulouse 1 Capitole, 2016)

Jessica was raised in a single-parent household and attended local state comprehensive schools in the North-West of England. She is the first in her family to be called to the Bar.

Jessica is committed to access to justice and has provided pro bono advice on several claims for judicial review on an urgent and non-urgent basis. She is happy to accept instructions pro bono in appropriate cases. In 2024, Jessica was nominated as Junior Pro Bono Barrister of the Year.

In her free time, Jessica enjoys rock climbing, hiking, and playing the piano.