Oliver specialises in the Court of Protection and is instructed by the full range of parties: NHS bodies, local authorities, the Official Solicitor and other litigation friends, and family members. He has particular expertise in the following matters: 

(1) Medical treatment cases

Oliver is instructed in cases concerning medical treatment of babies, children and adults. He brings a delicate approach to families in situations of crisis, an ability to digest complex clinical evidence quickly, and sensitive cross-examination of clinicians. Cases of note: 

• Acting for the NHS body in a declaration of death case: Re G [2024] EWHC 1288 (Fam);
• Acting for the NHS body in an eating disorder case: Re AB [2025] EWCOP 24 (T3);
• Acting for the family of an autistic woman with autism. On a pro bono and direct-access basis across hearings spanning five months, the court overturned a previous order that prevented life-saving treatment: Re Patricia [2025] EWCOP 30 (T3);
• Acting with Asma Nizami in an withdrawal of life-sustaining treatment of a baby. His solicitor said Oliver went “above and beyond” by visiting the parents and the baby in hospital the day before the hearing, which enabled him to understand the clients’ perspectives and to make sure their views were conveyed to the court: Re Baby Z [2025] EWHC 2100 (Fam).
• Acting for the mother of a cancer patient who had mental health issues: Re NT [2025] EWCOP 44 (T3); 

(2) Coercive control cases 

Oliver is regularly instructed in cases of great complexity where a person behaves in a coercive and controlling way against P, and where P is being harmed. He provides rapid and succinct advice to local authorities about potential applications to the Court of Protection (including property and affairs applications) or under the inherent jurisdiction of the High Court. Oliver advises on multi-agency collaboration and safeguarding responses.

Perpetrator tactics include making lasting powers of attorney (LPA), altering P‘s will, transferring P’s property, preventing social workers’ from accessing P, restricting P’s contact with others, controlling internet and social media, and denying P care. Oliver provides clients with rapid advice in urgent cases, suggesting practical legal strategies to stop this insidious form of domestic abuse, ensuring the safety and wellbeing of the victim/survivor. 

Oliver is the author of the book Coercive Control and Vulnerable Adults: Law and Practice in the Court of Protection and under the Inherent Jurisdiction of the High Court (Bloomsbury, 2026). In her Foreword, King LJ wrote that the text is an “an authoritative work covering all aspects of this important topic.” In his review, Alex Ruck Keene KC (Hon) said “this extraordinarily practical and comprehensive book which should be on the bookshelf of every practitioner who appears before the Court of Protection.” Emma Sutton KC  wrote that the book “will undoubtedly strengthen the skillset of even the most seasoned legal professional.”

Cases of note: 

• Re BR (unreported, 2023): represented the victim of decades-long intimate partner abuse across three years of proceedings.
• Re CA (Fact Finding - Capacity - Inherent Jurisdiction - Injunctive Relief) [2024] EWCOP 64: Oliver represented the local authority in a coercive control case that involved capacity hearing, best interests decisions, inherent jurisdiction orders, injunctions, a committal for contempt of court, and a reporting restrictions application.
• Re CN (unreported, 2025): represented a young woman whose mother neglected her, and sought to make every decision for her.
• Re DR (unreported, 2026): represented a man in his 60s with learning disabilities who was the victim of remote coercive control by his brother who lived abroad.
• Re BH (unreported, 2026): acted for a local authority to protect an older woman whose ‘friend’ had coerced her into changing her will and transferring her property.
• Re MR (unreported, 2026), acted for a local authority concerning an older woman whose son prevented her contact with other family members. 

(3) Learning disability and autism cases 

Oliver was one of a three counsel team who acted for the charity intervenors in A Reference by the Attorney General for Northern Ireland [2026] UKSC 16 that changed the definition of a deprivation of liberty. His explainer video is here. He can provide rapid advice and representation in cases where there is a doubt as to whether P is deprived of their liberty.

Cases about those with learning disabilities often involve entrenched conflict between the person’s family and social workers. Oliver’s calm and solution-oriented approaches defuse often fraught situations, leading to resolution. For example, in Re HG (unreported, 2024), Oliver represented a young man with learning disabilities who had been removed from his home. Oliver facilitated an in-person RTM where he used conflict resolution skills to encourage listening and appreciation of others’ perspectives. This led to the local authority changing its mind and agreeing on a move home. 

Oliver represented the young man in Re ZZ (Capacity) [2023] EWCOP 61 and on appeal led by Sophia Roper KC before Theis J at [2024] EWCOP 21, in a complex capacity case concerning ADHD, impulse control and sexual relations.

Oliver led Jordan Briggs in Re XY [2025] EWCOP 55 (T2) before the Senior Judge who clarified that decisions about internet and social media sit outside personal welfare deputyship orders. 

Oliver deals with the transition of 16- and 17-year-old disabled children into adult care regimes and from the family court to the Court of Protection. These cases often involve risk, including absconding, becoming victims of sexual abuse or online harm. In Re JW (unreported, 2026), Oliver represented a man with learning disabilities who was at risk of criminal offending, and at risk of losing his home through hoarding behaviours. In Re Tony Hickmott [2021] EWCOP 63, Oliver represented the applicant parents of a man who spent 21 years detained in a hospital under the Mental Health Act. The Senior Judge oversaw a prolonged four-year discharge planning process. 

Oliver has expertise on the interplay between the Mental Health Act 1983 and the Mental Capacity Act 2005 in the context of learning disability and autism. He has been working on law efforts since 1999 when he worked as a legal assistant for the Genevra Richardson Committee. During debates of the Mental Health Bill 2025, his work was cited on in a speech in the House of Lords, and in the report of the Joint Committee on Human Rights. 

(4) Other cases 

Oliver has ‘prosecuted’ committal hearings on behalf of local authorities, for example, Re CA [2025] EWCOP 15 (T3). He has defended committals on behalf of the contemnor, for example, Sunderland City Council v Lioubov Macpherson [2023] EWCOP 3. Oliver led Beth Grossman in the Court of Appeal case of Lioubov MacPherson v Sunderland City Council [2024] EWCA Civ 1579. They represented the appellant in an appeal against a committal to prison for civil contempt. The Court of Appeal found reason to believe that the appellant lacked capacity to conduct the appeal, and sent the matter back to the Court of Protection where Theis J determined the appellant had capacity: [2025] EWCOP 18.

He accepts instructions under the Mental Health Act 1983, including applications by patients in secure hospitals to the First-tier Tribunal (Mental Health), appeals to the Upper Tribunal, and applications to displace a nearest relative. 

He is Consultant Editor for Halsbury Law’s ‘Mental Health and Capacity’ with Leonie Hirst and Danielle Waddoup (2021). He is the General Editor of Atkin’s Court Forms ‘Court of Protection’ (2026). 

He is Co-Chair of the national charity Respond, which provides psychotherapy to autistic people and people with learning disabilities who have experienced trauma. And he is a trustee of the British Institute for Learning Disabilities. 

Oliver has extensive experience of strategic international disability rights litigation. For over a decade until 2017 he was Executive Director of the NGO Validity, where he spearheaded a series of successful disability rights test cases in the European Court of Human Rights from countries in central and eastern Europe. These include Shtukaturov v. Russia (2008) and Stanev v. Bulgaria (2012), both cited by the UK Supreme Court. Having participated in the drafting of the UN Convention on the Rights of Persons with Disabilities, he advises governments and NGOs on its implementation. 

Oliver accepts instructions in inquests that touch on healthcare, social care or disability. He represents bereaved families, NHS Trusts and other interested persons and has appeared in high-profile inquests that have criminal, regulatory and media aspects. He is an experienced jury advocate and has appeared in many Article 2 inquests. He is also experienced in challenging Coronial decisions by way of judicial review. In the Covid Inquiry, Oliver represented the Covid-19 Bereaved Families for Justice in Module 3 (healthcare).

“Oliver has a strength in understanding healthcare-related inquests.”—Chambers and Partners, 2025

Recent cases include:

• Inquest into the death of Marcus Hanlin, Avon, April 2024. Left unattended, Marcus inhaled uncooked rice and swallowed two conkers in a care home run by the Brandon Trust. Conclusion of accident contributed to by neglect. News item here. 
   
• Inquest into the death of Matthew Caseby, Birmingham, April 2022. Article 2 with a jury. Narrative conclusion critical of the Priory Woodbourne Hospital whose neglect contributed to Matthew's death. Prevention of Future Deaths reports were issued to the Secretary of State for Health and Social Care and the Priory Group. News item here.
   
• Inquest into death of Aaron Clamp, Reading Coroner's Court, Article 2 with a jury, February 2022: Narrative conclusion that Aaron died while on 1-to-1 observation in long-term segregation in Broadmoor Hospital and that there was "a serious failure in the timely manner to recognise and reduce the level of risk and a serious failure to recognise and execute the steps" to reduce the risk. News item here.  
   
• Inquest into death of Manon Jones, Pontipridd Coroner's Court, January 2022: Critical narrative conclusion in an Article 2 case that 16-year-old Manon Jones died in a Child and Adolescent Mental Health Services (CAMHS) unit on 15-minute observations when she "ought to have been on 1:1 observation levels pending a further assessment”. News item here.

At the international level, Oliver oversaw a third party intervention in Centre for Legal Resources v. Romania (2014), a case brought by a Romanian NGO in the European Court of Human Rights. This is a leading case on the right to life under Article 2 of the European Convention on Human Rights and access to justice for people with mental disabilities. The Court found that an NGO could pursue an application on behalf of a man who died in a psychiatric hospital and had no next of kin. 

Oliver regularly advises on health and social care provision and accepts instructions in clinical negligence cases across the range of medical specialisms. 

His niche practice is in relation to Human Rights Act and negligence claims about the care and treatment of people with mental health issues, learning disabilities, and/or autism in schools, prisons, psychiatric hospitals, care homes, and the community. Recent cases include: 

Re MJ – HRA claim on behalf of three family members who developed PTSD following the death of a teenage girl who died by suicide in a CAMHS unit. 

Re AP – Led by Jamie Burton KC, Oliver represented the family of AP, a man who was detained in a seclusion suite for 340 days. The case settled. Press release here.

Re Jamie Newcombe – Oliver represented an autistic man who was detained under the MHA by a private hospital. There, staff broke his arm using an inappropriate restraint, and mis-medicated him, and as a result, Jamie developed PTSD. The case settled. Press release here. 

Re JW – Oliver represented a woman with learning disabilities who was raped by a man in a care home, as the care home owner and the local authority failed to risk assess the man. The case settled.

Oliver has conducted confidential independent investigations for health and social care entities. Supplementing his legal training, Oliver has a Master of Public Administration (MPA) and draws on more than a decade of experience as a charity CEO and his experience as a trustee, background that provides an understanding of governance, human resources, communications, and management problems in organisations.

Complementing these civil claims and investigations, Oliver draws on his experience of medical treatment cases in the Court of Protection and the Family Division. He has a healthcare-related inquest practice. He sits as a Chair of Independent Review Panels for NHS England in relation to NHS Continuing Healthcare. 

Oliver is regularly instructed to advise on judicial reviews, including those related to provision of healthcare and in respect of the Mental Health Act 1983, the Care Act 2014 and the Equality Act 2010.

Oliver has worked in international disability and mental health law and policy since 2001 and is recognised as a leading expert. He has particular expertise with the UN Convention on the Rights of Persons with Disabilities (CRPD), having participated in its negotiation in 2006. Oliver has carried out human rights monitoring and delivered training in over twenty countries in Europe, Africa, Asia, and Latin America. 

Oliver accepts instructions for advisory work, research, training, and representation on all matters of disability and mental health law. His clients have included governments, the judiciary, NGOs, philanthropic organisations, corporations, and UN bodies.

Oliver has litigated, trained, and written about children’s rights, mental health law, monitoring closed institutions (psychiatric hospitals, social care institutions, children’s homes), equality and non-discrimination, community living, guardianship and legal capacity, political participation, and access to justice. He has a particular interest in preventing and litigating ill-treatment, including sexual violence, psychiatric coercion, and conditions of detention. 

In 2021, Oliver was the lead author on the United Nations Development Programme (UNDP) report Political Participation of Persons with Intellectual or Psychosocial Disabilities. In 2022, he trained judges in Georgia on disability law, and he was one of five global experts appointed to assess CRPD implementation in Taiwan. In 2023, he wrote a report on children with disabilities for UNICEF Viet Nam and a report about deaf drivers for UNDP Georgia. His ongoing work includes supporting the judiciary in Taiwan to develop a mental health tribunal system. He is on UNDP's panel of experts on mental healthcare.

After finishing pupillage in 2001, Oliver was appointed Legal Director of the international legal advocacy NGO Validity (formerly the Mental Disability Advocacy Centre, or MDAC), and in 2006 became its Executive Director, a position he held until 2017 when he returned to the UK Bar. 

In 2006, he co-authored the book Mental Disability and the European Convention on Human Rights. As one of the drafters of the CRPD, he has written extensively on its implementation, including: 

• “Supranational Human Rights Bodies and Protecting the Rights of People With Disabilities in the COVID-19 Pandemic” in the European Human Rights Law Review in 2020; 
   
• with Soumitra Pathare, “Chronic illness, disability and mental health” in Foundations of Global Health and Human Rights, edited by Benjamin Meier and Lawrence Gostin, OUP 2020; and 
   
• with Genevra Richardson, "The right to live independently and be included in the community", International Journal of Law and Psychiatry, Vol 69, March-April 2020.

At MDAC, Oliver oversaw the world’s largest multi-country docket of disability rights test cases. Under his leadership, MDAC represented applicants or acted as amicus curiae in around 15 cases before the European Court of Human Rights, as well as numerous cases in constitutional courts and other domestic proceedings, including in Bulgaria, the Czech Republic, Russia, and Slovakia.  

Oliver has advocated before several human rights bodies, including the UN Human Rights Committee, the UN Committee against Torture, the UN Subcommittee for the Prevention of Torture, the UN Committee on the Rights of the Child, and the UN Committee on the Rights of Persons with Disabilities. He has advised UN Special Rapporteurs, and he has worked on projects with the UN Office of the High Commissioner for Human Rights (OHCHR), UNDP, UNICEF, and the WHO. In Europe, Oliver has conducted advocacy at the European Commission, the European Parliament, the Council of Europe’s Parliamentary Assembly, the Committee for the Prevention of Torture, and the Commissioner for Human Rights. In 2011, he led a successful international campaign that resulted in the Venice Commission reversing its previous recommendation that governments deny people under guardianship the right to vote.

For a full list of Oliver’s publications, see ResearchGate. Oliver blogs here. Recent publications include:

Oliver Lewis (2020) “Supranational Human Rights Bodies and Protecting the Rights of People With Disabilities in the COVID-19 Pandemic”, European Human Rights Law Review, September

Oliver Lewis and Soumitra Pathare (2020) “Chronic illness, disability and mental health” in Foundations of Global Health and Human Rights, Benjamin Meier and Lawrence Gostin (eds), OUP

Oliver Lewis and Genevra Richardson (2020) The right to live independently and be included in the community, International Journal of Law and Psychiatry, Vol 69, March-April 2020

Oliver Lewis (2018) “Council of Europe” in Lisa Waddington and Anna Lawson (eds) The UN Convention on the Rights of Persons with Disabilities in Practice, OUP

Ann Campbell and Oliver Lewis, “Violence and abuse against people with disabilities: A comparison of the approaches of the European Court of Human Rights and the United Nations Committee on the Rights of Persons with Disabilities”, International Journal of Law and Psychiatry, Volume 53, July–August 2017, Pages 45-58

Felicity Callard and Oliver Lewis (2017) “The World Psychiatric Association’s “Bill of Rights”: A curious contribution to human rights”, International Journal of Mental Health, 46:3, 157-167