Cecilia Ivimy KC

Professional Summary

Called 1995 Appointed KC 2025

Contact Details

T +44 (0)20 7632 8500 Clerk Michael Smith Clerk Thomas Belcher Clerk Jake Foote E Contact Clerks

Cecilia has an extensive practice in public and administrative law, human rights, information law, commercial regulatory judicial review, online safety, and social security.

Cecilia’s clients include private clients, regulators, public authorities and central government departments. She has represented and advised clients at all levels in the domestic courts and in the European Court of Human Rights.

For many years Cecilia was ranked as a leading junior in Public and Administrative Law and Civil Liberties and from 2025 has been ranked as a new silk. Prior to taking silk, Cecilia was a member of the Attorney General’s A Panel of Counsel.

Specialisms

Public

“Concise, really dissects the case and hits the key arguments. She is highly persuasive”. Chambers and Partners 2025

Cecilia is instructed in complex, sensitive and politically contentious public law proceedings. She acts for private clients, central and local government, regulators, ombudsmen, local authorities and universities. From 2025 she has been ranked as a new silk in administrative and public law, having previously been ranked as a leading junior.

Key areas include: judicial review of legislation and policies; Convention rights; commercial regulatory judicial review, including online safety and financial services; information law and data protection; discrimination law; the public sector equality duty; and social security, child maintenance and statutory pensions appeals.

Some significant public law cases from the last 4 years have concerned:

Financial services – a pre-action challenge on the lawfulness of regulation of copper trading on the London Metal Exchange, raising environmental and proceeds of crime issues
Online safety – judicial review of categorisation regulations made under the Online Safety Act; acting for the SoS for Science, Innovation and Technology
Convention rights/judicial review – two linked challenges to the Regulations establishing the Infected Blood Compensation Scheme; acting for Minister for the Cabinet Office
Social security – the proper interpretation of Universal Credit temporary absence rules, A1P1 and Article 14; acting for SoS for Work and Pensions
Convention rights – whether tax information notice proceedings fall within Article 6 ECHR and the proper approach to declarations of incompatibility; acting for the Attorney General for Jersey
Constitutional/international law – scope of Civil servants’ obligations to comply with international law under the Civil Service Code; acting for the Minister for the Cabinet Office
Discrimination/Convention rights – whether the DWP has positive obligations under the ECHR to collect and enforce payment of child maintenance; acting for the SoS for Work and Pensions
Financial Services – whether authorisation by the Financial Conduct Authority of the prospectus of an oil and gas company was unlawful because of a failure properly to disclose climate-related risks; acting for the FCA
Social Security – the lawfulness of Government policy on recovery of benefits overpayments; acting for the SoS for Work and Pensions
Constitutional law – lawfulness of the Prime Minister’s decision that the Home Secretary had not engaged in “bullying”; acting for the Prime Minister
Equalities – the lawfulness of guidance issued by the Office for National Statistics on answering the question “what is your sex” in the Census; acting for the ONS

In the first part of her career (Cecilia did not practice between 2010 and 2020) Cecilia appeared as lead junior in some of the most high profile public law appeals, including eight appeals before the House of Lords. Her cases covered:

The application of the Human Rights Act to private care homes
Deaths and detention of civilians in Iraq and Afghanistan
Legality of UK implementation of UN sanctions regimes
Investigation of deaths of patients in secure hospitals
Lawfulness of control orders against suspected terrorists

Public International Law

Cecilia has experience on the inter-relationship between international and domestic human rights law, including in relation to the ECHR, the ICCPR, the Geneva Conventions and international humanitarian law and resolutions of the UN Security Council. She has represented the United Kingdom in multiple cases before the ECtHR.

She has advised and represented the UK Government in relation to issues arising out of military action in Iraq and Afghanistan and in relation to terrorism, including control orders and sanctions regimes.

Recent advice includes advice on domestic and international law implications of restricting public bodies’ powers to act in relation to boycotts, divestment and sanction policies and practices; and advice on legislation governing Article 5 deprivation of liberty rights extra-territorially.

Cecilia co-authored the 2018 report of an inquiry by an All Party Parliamentary Group into the legality and practice of the UK Government’s use of lethal drone and its co-operation with other states’ use of lethal drones.

Human Rights

“Cecilia has a deep knowledge of human rights and equality law. She is incredibly quick to grasp a point and her advocacy is clear, precise and very responsive to judges.” Chambers and Partners 2025

Cecilia has extensive experience in human rights law. She has acted in Convention rights cases at all levels in the domestic courts and in multiple appeals before the ECtHR. She acts for private clients, public authorities and central and local government. Areas covered include: online safety, regulatory action, welfare benefits, education, pensions, sanctions, proceeds of crime, prisons and secure hospitals, and military action abroad.

Recent significant cases have concerned:

The Online Safety Act – whether categorisation regulations infringe the Article 10 rights; acting for the Secretary of State for Science, Innovation and Technology
The Infected Blood Compensation Scheme – whether e infringe Article 14 rights of persons infected with Hepatitis C; acting for Minister for the Cabinet Office
Benefits legislation- whether non-payment of universal credit to claimants absent abroad due to health reasons infringes A1P1, Article 8 and Article 14; acting for Secretary of State for Work and Pensions
Benefits legislation – whether support for home owners infringes A1P1 and Article 14; acting for Secretary of State for Work and Pensions
Prisons – whether the non-disclosure of information which led to a prisoner being recalled and not re-released infringed Article 5 rights; acting for Secretary of State for Justice
Child maintenance – whether the DWP has positive obligations under the ECHR to collect and enforce payment of child maintenance, in particular in cases of domestic violence; acting for the Secretary of State for Work and Pensions
COVID 19 – whether COVID travel isolation requirements were irrational, disproportionate, or breached Articles 5 and 8; acting for the Secretary of State for Health and Transport
Local Government – A1P1 compatibility of public sector “Exit Payment” regulations and their effect on the Local Government Pension Scheme; acting for the claimants including a public sector union

In the first part of her career (Cecilia did not practice between 2010 and 2020) Cecilia appeared as lead junior in multiple leading human rights appeals in the House of Lords and the Grand Chamber of the European Court of Human Rights. Subjects included:

Care homes – whether public authorities under the HRA
Iraq and Afghanistan military action – application of the HRA and ECHR to deaths and detention of civilians
Investigations – Article 2 duty to investigate deaths of patients in secure hospitals
Terrorism control orders – compatibility with Articles 5 and 8
Privacy rights and data retention – compatibility of disclosure of spent convictions with Article 8

Information

Cecilia regularly represents central government, local government and other public bodies as well as private clients in sensitive and complex FOIA and EIR appeals, and in complex cases involving the interaction of public law, information law and data protection. Recent significant appeals concerned:

Contempt proceedings in the Upper Tribunal arising out of non-compliance with a FTT decision; acting for a private client
A pre-action JR challenge to the proposed disclosure of an application to the MHRA for medicines marketing authorisation; acting for a private client
Disputed disclosure of data protection impact assessments on the use of advanced analytics to determine fraud in the benefit system; acting for the Department for Work and Pensions
Sensitive FOIA appeals concerning:
Ministerial communications on reform of access to information law
Communications between HM Treasury and the Financial Conduct Authority on COVID 19 business grants
Submissions from every Government Department, the Attorney General and No. 10 on reform of judicial review law
Cabinet Office papers and principles and scope of collective responsibility
Environmental information relating to planning applications
Section 14 (vexatious requests), including appeals involving harassment, social media campaigns and employment disputes.

Cases

Recent public and human rights law cases

Wikimedia Foundation v Secretary of State for Science, Innovation and Technology
King’s Bench Division (Administrative Court) [2025] EWHC 2086 (Admin) 11 Aug 2025
Whether categorisation regulations made under the Online Safety Act were irrational or infringed Convention rights; acting for The Secretary of State for Science Innovation and Technology

KK v Secretary of State for Work and Pensions
Upper Tribunal (Administrative Appeals Chamber) [2025] UKUT 259 (AAC) 1 Aug 2025
Whether regulations governing right to Universal Credit during periods of temporary absence for medical reasons infringed Article 14 ECHR

Imperium Trustees Ltd v Jersey Competent Authority
Privy Council (Jersey) [2025] UKPC 28 24 Jun 2025
Whether judicial review proceedings concerning notices to produce tax information fall within Article 6(1) ECHR; acting for the Attorney General for Jersey

R. (on the application of Kaur) v Birmingham City University
King’s Bench Division (Administrative Court) [2024] EWHC 3185 (Admin) 9 Dec 2024
Lawfulness of withdrawal of immigration sponsorship from university students; acting for Birmingham City University

R. (on the application of FDA) v Minister for the Cabinet Office
King’s Bench Division (Administrative Court) | [2024] EWHC 1729 (Admin) | 5 Jul 2024
Proper scope of civil servants’ obligation to comply with the law, including international law, under the Civil Service Code. Civil servants would act in accordance with the obligation if they implemented a minister’s decision to remove a person to Rwanda notwithstanding that the ECtHR had ruled that the person should not be removed; acting for Minister for the Cabinet Office

R. (on the application of AA) v Secretary of State for Work and Pensions
Court of Appeal (Civil Division) | [2024] EWCA Civ 595 | 29 Apr 2024
Permission to appeal against decision that Child Maintenance Service policy did not breach Article 8 positive obligations to protect victims of domestic violence refused; acting for the Secretary of State for Work and Pensions

R. (Scott) v Secretary of State for Justice
King’s Bench Division (Administrative Court) | [2024] EWHC 855 (Admin) | 18 Apr 2024
Decision to recall and not to re-release prisoner convicted of serious domestic violence offences and to withhold name of informant and details of information which led to recall was lawful; acting for Secretary of State for Justice

Swindon Borough Council v Abrook
Court of Appeal (Civil Division) | [2024] EWCA Civ 230 | 8 Mar 2024
Court of Appeal guidance on the definition of “anti-social behaviour” in the Anti-social Behaviour, Crime and Policing Act 2014 and proper approach to making an anti-social behaviour injunction under the Act; acting as advocate to the Court, appointed by the Attorney General

R. (on the application of Ingold) v Secretary of State for Work and Pensions
King’s Bench Division (Administrative Court) | [2023] EWHC 3207 (Admin) | 15 Dec 2023
Child maintenance service operation and policies not contrary to ECHR Article 8, 14 or A1P1; acting for the Secretary of State for Work and Pensions

R. (on the application of ClientEarth) v Financial Conduct Authority
King’s Bench Division (Administrative Court) | [2023] EWHC 3301 (Admin) | 13 Dec 2023
FCA’s approval of prospectus of an oil and gas company not unlawful having regard to disclosures of climate-related risks; claim not within the Aarhus Convention; acting for the FCA

R. (on the application of K) v Secretary of State for Work and Pensions
King’s Bench Division (Administrative Court) | [2023] EWHC 233 (Admin) | 7 Feb 2023
DWP waiver policy with respect to benefit overpayments lawful; individual decision not to waive unlawful; acting for Secretary of State for Work and Pensions

R. (on the application of FDA) v Prime Minister
Divisional Court | [2021] EWHC 3279 (Admin) | 6 Dec 2021
Prime Minister’s decision that bullying by the Home Secretary had not breached the Ministerial Code was lawful; acting for the Prime Minister.

R. (on the application of Fair Play for Women Ltd) v UK Statistics Authority
Queen’s Bench Division (Administrative Court) | [2021] EWHC 940 (Admin) | 9 Mar 2021
Interim injunction; lawfulness of guidance on question “what is your sex?” in the 2021 census; acting the UK Statistics Authority

R. (on the application of British Airways & ors) v Secretary of State for Health
Divisional Court | July 2020 | (settled at hearing)
Lawfulness of Covid-19 travel restrictions; acting for the Secretary of State for Health

Recent information law cases

Greenwich RLBC v Information Commissioner
First-tier Tribunal (General Regulatory Chamber) [2025] UKFTT 85 (GRC) 4 Feb 2025
Proper application of the legal professional privilege exception under the EIR to draft planning documents; acting for Greenwich RLBC

Boswell v Information Commissioner
First-tier Tribunal (General Regulatory Chamber) [2024] UKFTT 779 (GRC) 4 Sep 2024
Whether ONS entitled to refuse requests under section 14 vexatiousness; acting for ONS

Corderoy v Information Commissioner & Cabinet Office
First-tier Tribunal (General Regulatory Chamber) | [2024] UKFTT 473 (GRC) | 5 Jun 2024
The Cabinet Office was entitled to withhold ministerial communications discussing how the Government should respond to the Information Commissioner’s report into reform of access to information law; acting for the Cabinet Office

Perrys Motor Sales/Perrys Group Ltd v Information Commissioner & HM Treasury
First-tier Tribunal (General Regulatory Chamber) | [2024] UKFTT 62 (GRC) | 26 Jan 2024
Discussions between HM Treasury and the FCA concerning legal and policy response to Covid-related business insurance interruption claims exempt from disclosure; acting for HM Treasury

Sloan v Information Commissioner
First-tier Tribunal (General Regulatory Chamber) | [2023] UKFTT 342 (GRC) | 30 Mar 2023
Information about Cabinet Committee meetings exempt from disclosure having regard to need to maintain ministerial collective responsibility; acting for the Cabinet Office

South Gloucestershire DC v Information Commissioner
First-tier Tribunal (General Regulatory Chamber) | [2022] UKFTT 445 (GRC) | 2 Dec 2022
Information related to new station development project exempt from disclosure under the EIR; acting for South Gloucestershire DC

Public Law Project v Information Commissioner and Ministry of Justice
First-tier Tribunal (General Regulatory Chamber) | [2022] 3 WLUK 568 | 25 Mar 2022
Submissions from 13 Secretaries of State on reform of judicial review law exempt from disclosure, having regard to principles of collective responsibility; acting for the Ministry of Justice

Ministry of Justice v Information Commissioner
First-tier Tribunal (General Regulatory Chamber) | [2021] 3 WLUK 568 | 7 July 2021
Information held by Chief Executive of HM Prison & Probation Service about release arrangements for high-profile prisoner exempt from disclosure; acting for the Ministry of Justice

Main Cases before Career Break

Al-Jedda v United Kingdom (27021/08)
European Court of Human Rights (Grand Chamber) | (2011) 53 EHRR 23 | 7 Jul 2011
Compatibility with ECHR Article 5 of internment of citizen in Iraq pursuant to UNSC Resolution; acting for United Kingdom

Al-Skeini v United Kingdom (55721/07)
European Court of Human Rights (Grand Chamber) | (2011) 53 EHRR 18 | 7 Jul 2011
Extra-territorial application of ECHR Article 2 and 3 to killing of Iraqi nationals in Iraq by UK forces; acting for United Kingdom

Mousa v Secretary of State for Defence
Divisional Court | [2010] EWHC 1823 (Admin) | 16 Jul 2010
Whether state under duty to conduct public inquiry into alleged mistreatment of Iraqi citizens in Iraq by British military; acting for Secretary of State for Defence

Chief Constable of Humberside v Information Commissioner
Court of Appeal (Civil Division) | [2009] EWCA Civ 1079 | 19 Oct 2009
Data protection and ECHR rights did not require police to delete old convictions from the Police National Computer; acting for intervener, Secretary of State for Justice

(on the application of Willcox) v Secretary of State for Justice
Divisional Court | [2009] EWHC 1483 (Admin) | 1 Jul 2009
ECHR rights did not require release of prisoner transferred from Thai prison; acting for Secretary of State for Justice

A v United Kingdom (3455/05)
European Court of Human Rights (Grand Chamber) | (2009) 49 EHRR 29 | 19 February 2009
Compatibility of closed material procedure in Special Immigration Appeals Commission with ECHR Article 6; acting for United Kingdom

Secretary of State for the Home Department v F
House of Lords | [2009] UKHL 28 | 10 Jun 2009
Compatibility with ECHR Article 6 of closed procedures in anti-terrorism control order proceedings; acting for Secretary of State for Home Department

Savage v South Essex Partnership NHS Foundation Trust
House of Lords | [2008] UKHL 74 | 10 Dec 2008
Obligations under Article 2 ECHR owed to detained mental health patients; acting for intervener Secretary of State for Health

(on the application of JL) v Secretary of State for the Home Department
House of Lords | [2008] UKHL 68 | 26 Nov 2008
Obligation to investigate suicide of prisoner in custody under Article 2 ECHR; Acting for Secretary of State for Home Department

(on the application of M) v HM Treasury
House of Lords | [2008] UKHL 26 | 30 Apr 2008
Lawfulness of UK implementation of UN sanctions regime; acting for HM Treasury

Secretary of State for the Home Department v JJ, E & MB
House of Lords | [2007] UKHL 45, 46, 47 | 31 Oct 2007
Whether anti-terrorism control order regimes comply with ECHR Articles 5 and 6; acting for Secretary of State for Home Department

L v Birmingham City Council
House of Lords | [2007] UKHL 27 | 20 Jun 2007
Whether privately owned care home exercising public functions for the purpose of the HRA; acting for intervener, Secretary of State for Constitutional Affairs

(on the application of Al-Skeini) v Secretary of State for Defence
House of Lords | [2007] UKHL 26 | 13 Jun 2007
Whether the HRA and ECHR applied extra-territorially to killing of Iraqi nationals in Iraq by UK forces; acting for Secretary of State for Defence

Recommendations

Deep knowledge of human rights and equality law. She is incredibly quick to grasp a point and her advocacy is clear, precise and very responsive to judges.- Chambers & Partners 2025

Clear, thorough, responsive and intellectually agile with excellent judgement.- Chambers & Partners 2025

Excellent in her client communication; she is always approachable.- Chambers & Partners 2025

Very concise, really dissects the case and hits the key arguments. She is highly persuasive.- Chambers & Partners 2025

“She is an excellent barrister; she grasps complex matters quickly and provides timely advice. Clients trust her judgement.” – Chambers & Partners 2023

“A knowledgeable practitioner who comes up with novel arguments in a very tactical way.” – Chambers & Partners 2023

“Cecilia Ivimy is a sought-after barrister with wide-ranging experience acting in public law challenges on behalf of central government, local authorities and public sector unions. She has extensive experience in judicial review and regulatory proceedings.” – Chambers and Partners 2023

“She is very responsive, her drafting is incredible and her advocacy is very strong. She can also identify issues others might miss and narrow cases down to what’s really important.” – Chambers & Partners 2022

Education

Cecilia has a first class degree from Oxford University and a distinction in the diploma in law from City University.

Other

Cecilia is an an accredited CEDR mediator. Cecilia also has experience as a mediation advocate in a range of contexts including community care and employment.