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.

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.

  • Quotation symbolCecilia is consistently user-friendly. She is clear, thorough, prompt, intellectually agile and has excellent judgement.

    Quotation symbolChambers & Partners, 2026

  • Quotation symbolCecilia is an outstanding barrister with fantastic attention to detail and excellent client service.

    Quotation symbolChambers & Partners, 2026

  • Quotation symbolCecilia is a real expert in this field. Her drafting is clear and persuasive, and she is a pleasure to work with.

    Quotation symbolChambers & Partners, 2026

Expertise

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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; Convention rights; regulatory work, including online safety and financial services; information law and data protection; equalities law; social security and child maintenance.

Cecilia also has a busy advisory practice. She regularly advises on public authority vires issues, and on regulatory and public sector transactions, investigations and reviews.

Some significant recent public law cases include:

R (TSZ) v Minister for the Cabinet Office [2025] (Admin)
Regulations establishing infected blood compensation scheme were lawful and did not infringe Article 14 ECHR; acting for Minister for the Cabinet Office

R (Wikimedia Foundation) v Secretary of State for Science, Innovation and Technology [2025] EWHC 2086 (Admin)
Categorisation regulations made under the Online Safety Act were not irrational and did not infringe Convention rights; acting for The Secretary of State for Science Innovation and Technology

R (KK) v Secretary of State for Work and Pensions [2025] UKUT 259 (AAC)
Regulations governing right to Universal Credit during periods of temporary absence for medical reasons did not infringe Article 14 ECHR

R (Imperium Trustees Ltd) v Jersey Competent Authority [2025] UKPC 28
Article 6(1) did not apply to judicial review proceedings concerning notices to produce tax information; guidance on declarations of incompatibility; acting for the Attorney General for Jersey

R (FDA) v Minister for the Cabinet Office [2024] EWHC 1729 (Admin)
Proper scope of civil servants’ obligation to comply with the law, including international law, under the Civil Service Code; acting for Minister for the Cabinet Office

 R (AA) v Secretary of State for Work and Pensions [2024] EWCA Civ 595
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 [2024] EWHC 855 (Admin)
Decision to recall and not to re-release prisoner convicted of serious domestic violence offences and to withhold name of informant was lawful; acting for Secretary of State for Justice

Swindon Borough Council v Abrook [2024] EWCA Civ 230
Court of Appeal guidance on the definition of “anti-social behaviour” in the Anti-social Behaviour, Crime and Policing Act 2014 and anti-social behaviour injunctions; acting as advocate to the Court, appointed by the Attorney General

R (Ingold) v Secretary of State for Work and Pensions [2023] EWHC 3207 (Admin)
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 (ClientEarth) v Financial Conduct Authority [2023] EWHC 3301 (Admin)
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 (K) v Secretary of State for Work and Pensions [2023] EWHC 233 (Admin)
DWP waiver policy with respect to benefit overpayments lawful; individual decision not to waive unlawful; acting for Secretary of State for Work and Pensions

(FDA) v Prime Minister [2021] EWHC 3279 (Admin)
Prime Minister’s decision that bullying by the Home Secretary had not breached the Ministerial Code was lawful; acting for the Prime Minister.

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

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  • Concise, really dissects the case and hits the key arguments.  She is highly persuasive

    Chambers & Partners 2025

  • A real expert in this field

    Chambers & Partners, 2026

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Cecilia is experienced in 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.

Cecilia’s advisory work includes advice on overseas military operations, international military agreements, terrorism, control orders, sanctions regimes, and boycotts and divestment.

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.

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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.

Cecilia also regularly advises on human rights issues arising in public authority and regulatory decisions and transactions, and human rights compatibility of proposed legislation and policies.

Some recent significant human rights cases include:

R (TSZ) v Minister for the Cabinet Office [2025]
Regulations establishing infected blood compensation scheme were lawful and did not infringe Article 14 ECHR; acting for Minister for the Cabinet Office

R (Wikimedia Foundation) v Secretary of State for Science, Innovation and Technology [2025] EWHC 2086 (Admin)
Categorisation regulations made under the Online Safety Act were not irrational and did not infringe Convention rights; acting for The Secretary of State for Science Innovation and Technology

R (KK) v Secretary of State for Work and Pensions [2025] UKUT 259 (AAC)
Regulations governing right to Universal Credit during periods of temporary absence for medical reasons did not infringe Article 14 ECHR

R (Imperium Trustees Ltd) v Jersey Competent Authority [2025] UKPC 28
Article 6(1) did not apply to judicial review proceedings concerning notices to produce tax information; guidance on declarations of incompatibility; acting for the Attorney General for Jersey

R (AA) v Secretary of State for Work and Pensions [2024] EWCA Civ 595
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 [2024] EWHC 855 (Admin)
Decision to recall and not to re-release prisoner convicted of serious domestic violence offences and to withhold name of informant was lawful and did not infringe Art 5 ECHR; acting for Secretary of State for Justice

R (Ingold) v Secretary of State for Work and Pensions [2023] EWHC 3207 (Admin)
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

In the first part of her career (Cecilia did not practice between 2010 and 2020) Cecilia was 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
  • Military action – application of the HRA and ECHR to overseas operations
  • 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

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  • 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 & Partners 2025

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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.

Cecilia also regularly advises on information law and data protection issues, in particular those arising in the context of public law transactions, investigations and reviews.

Recent significant appeals concerned:

  • Judicial review proceedings concerning Information Commissioner’s decision on data protection complaint; acting for Information Commissioner
  • 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 by regulator of commercially sensitive application for regulatory 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/EIR 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 and Reg 12(4)(b) (vexatious/manifestly unreasonable requests), including appeals involving harassment, campaigns, and social media and employment disputes.

Download Information, Technology & Media CV

ToggleRecent cases

 

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  21. 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

  22. 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

  23. 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

  24. 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

  25. 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

  26. 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

  27. (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

  28. 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

  29. 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

  30. 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

  31. (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

  32. (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

  33. 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

  34. 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

  35. (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

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Achievements

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

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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.

Insights&News

  1. News

    11KBW on both sides in judgment on ‘external eyes only’ confidentiality rings in procurement disputes

    View News

  2. News

    Silk Appointments: Cecilia Ivimy and Tom Cross

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  3. News

    2 Members of 11KBW approved for appointment as King’s Counsel

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  4. Articles

    Cecilia Ivimy and Oliver Jackson act in judicial review challenge to Child Maintenance Service

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  5. News

    Clive Sheldon KC’s report into the Armoured Cavalry Programme presented to Parliament

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  • Quotation symbol

    She is an excellent barrister; she grasps complex matters quickly and provides timely advice. Clients trust her judgement

    Chambers & Partners 2023

  • Quotation symbol

    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

  • Quotation symbol

    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

  • Quotation symbol

    Clear, thorough, responsive and intellectually agile with excellent judgement.

    Chambers & Partners 2025

  • Quotation symbol

    Excellent in her client communication; she is always approachable.

    Chambers & Partners 2025

  • Quotation symbol

    Very concise, really dissects the case and hits the key arguments. She is highly persuasive.

    Chambers & Partners 2025

  • Quotation symbol

    She is an excellent barrister; she grasps complex matters quickly and provides timely advice. Clients trust her judgement.

    Chambers & Partners 2023

  • Quotation symbol

    A knowledgeable practitioner who comes up with novel arguments in a very tactical way.

    Chambers & Partners 2023

  • Quotation symbol

    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 & Partners 2023