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“Her advocacy and drafting skills are unmatched, and she is always keen to make a real change with her work. She excels at working with vulnerable clients who are victims of torture, sexual violence, and other heinous crimes, and her passion for her work really shines through in her hard work and dedication to each and every case she works on.” – Legal 500, 2024

Career Profile

Antonia works across the fields of asylum, immigration, and public law, with specialisms in refugee, asylum law, and children’s rights. Before joining the Bar, she worked for NGOs, including the Refugee Council, and has more than 18 years’ experience working in support of refugee and migrant rights. 

Antonia is regularly instructed in the First-Tier and Upper Tribunals, High Court, and Court of Appeal on asylum and public law claims, with a particular focus on complex claims and those involving victims of torture and sexual violence. She is highly regarded for her ability to engage with particularly vulnerable clients and her detailed knowledge of country conditions and asylum policy. She is especially well placed to undertake cross-cutting work in the fields of immigration, children’s rights, and public law and works on complex country guidance cases and claims involving cessation/revocation of international protection.

Antonia is regularly instructed in public law challenges on behalf of unaccompanied asylum-seeking children whose age is disputed by the Home Office or local authorities; on the unlawful detention of putative children; and on asylum support challenges under the Immigration and Asylum Act 1999. In addition, she acts on behalf of adults and unaccompanied minors in challenges to trafficking decisions and unlawful detention claims. Antonia acts in criminal deportation, human rights claims, and EU law challenges and has extensive expertise in out-of-hours and urgent claims.

Antonia frequently speaks at public events on refugee and broader human rights issues. She regularly delivers training both for and in partnership with NGOs and community organisations, with a focus on the asylum system and issues affecting asylum-seeking and refugee clients. She is an advocacy trainer for the Honourable Society of Lincoln’s Inn. 

From 2018 to 2022, Antonia was appointed as counsel in the Independent Inquiry into Child Sexual Abuse (IICSA), led by Henrietta Hill KC, acting in the children outside the UK (Phase 2) and child sexual exploitation by organised networks investigations. 

Antonia was a finalist for Legal Aid Barrister of the Year in the Legal Aid Lawyer of the Year Awards in 2023. In 2024, she was ranked as a leading junior in immigration, administrative and public law, and community care by Chambers and Partners and as a leading junior in immigration law and court of protection and community care in the Legal 500.

What people are saying about Antonia

“Antonia is a truly outstanding advocate. She is sharp, knows her cases inside-out, and is measured and compelling in submissions. She is flawless.”—Legal 500, 2024 

“Antonia Benfield is renowned by peers for her strong advocacy and knowledge in the areas of public law, immigration, and asylum. She acts for vulnerable claimants, including individuals with mental health issues and asylum seekers. Age assessments and unlawful detention claims feature heavily in her practice.”—Chambers and Partners, 2024

“Antonia is an immensely impressive junior barrister. She is a dedicated fighter, and this shines through in her meticulous attention to detail and willingness to go the extra mile.”—Chambers and Partners, 2023

“Antonia is responsive and brilliant to work with.”—Chambers and Partners, 2023

“Go-to counsel for complex cases and those involving vulnerable clients. She is very sharp and will often pick up on issues others would miss. In court, she is a powerful advocate and fights fearlessly for her clients.”—Legal 500, 2023

“Antonia is unparalleled in her knowledge and expertise in age assessment disputes. She is extremely efficient and sharp.”—Legal 500, 2023

“She works incredibly hard. She has a calm and reassuring presence and is super clever.”—Chambers and Partners 2022

“She has extensive knowledge and is very thorough and quick to respond. She is incredibly passionate about her clients and is a delight to work with.”—Chambers and Partners 2022

“Antonia has excellent skills in picking up points that others would miss, her keen eye for detail is combined with her powerful advocacy.”—Legal 500, 2022

“She is extremely intelligent, a formidable opponent.”—Chambers and Partners, 2021

“Astonishingly bright. Antonia’s strengths include being incredibly fast to grasp all details of the case and having a mastery of every minute detail of the claim. She has amazing analytical skills.” — Legal 500, 2021

Immigration and Asylum Law

Antonia specialises in asylum and refugee law, representing both high-profile individuals and vulnerable clients, including those who have been victims of trafficking, serious human rights abuses, and torture. She has particular experience working with clients who have complex mental health problems.

She is well regarded for her extensive knowledge of asylum law and policy and her sensitivity in working with vulnerable clients. Antonia is dedicated to the advancement of refugee rights and regularly works for NGOs and law centres, which are in particular need of high-quality representation.

She has a particular interest in complex policy challenges in relation to the cessation and revocation of refugee status in line with UNHRC standards, cases of disputed and doubtful nationality, and in the interpretation of medico-legal reports as independent evidence of torture. 

Antonia is highly experienced in refugee claims from Sri Lanka, Eritrea, Afghanistan, Uganda, and the Democratic Republic of Congo. Her knowledge of country information is extensive, and she excels in presenting complex factual cases. 

Significant cases

KK and RS (Sur place activities: risk) Sri Lanka CG [2021] UKUT 0130 (IAC): Country guidance case addressing the risk to those who have been involved in sur place political activities in the United Kingdom in opposition to the Government of Sri Lanka. The case restated the protection framework and gave detailed consideration to the current human rights situation in Sri Lanka.  

KK and RS (Sri Lanka) v Secretary of State for the Home Department [2022] EWCA Civ 119: successfully defending the country guidance on Sri Lanka given by the Upper Tribunal following a wide-ranging appeal by the Secretary of State for the Home Department.

MST and Others (national service – risk categories) Eritrea CG [2016] UKUT 00443 (IAC) – country guidance case considering the risk on return for Eritrean nationals, in which the UNHCR acted as intervener. Considering whether there had been change in the country situation following a change in the Home Office’s policy to the human rights situation in the country. The case established that the risk categories for Eritrean asylum seekers should be maintained and extended to provide a protection against a breach of Article 4 (2) ECHR for those required to undertake national service in Eritrea which was found to constitute forced labour. 

Since 2023, Antonia has been instructed in the lead challenge to the refusal of protection to a group of Tamil asylum-seekers on Diego Garcia in the Chagos Islands, brought against the Commissioner of the British Indian Ocean Territory.

Administrative and Public Law

Antonia specialises in public and administrative law in immigration and asylum cases as well as in age-dispute/age-assessment challenges for asylum-seeking children, asylum support challenges, unlawful detention and trafficking claims.  In the field of asylum law, she is regularly instructed in asylum fresh claims.

Antonia has particular experience in judicial review challenges against local authorities and the Home Office on behalf of unaccompanied asylum-seeking children, including age dispute challenges, challenges to detention, termination of support, and dispersal and challenges to transfer under the National Transfer Scheme. She is presently instructed on a number of complex cases involving disputes between local authorities about the responsibility for unaccompanied asylum-seeking children.

Significant cases

R (ECPAT UK) v Kent County Council & Secretary of State for the Home Department [2023] EWHC 1953 (Admin): Successful challenge establishing that the use of hotel accommodation provided by the SSHD for unaccompanied asylum-seeking children was unlawful. 

R (MA & HT) v Secretary of State for the Home Department [2022] EWHC 98 (Admin): Successful challenge to the lawfulness of the Kent Intake Unit social worker guidance governing the conduct of age assessments for putative children while detained at the KIU. 

R (NB & Ors) v Secretary of State for the Home Department [2021] EWHC 1489 (Admin): Successful challenge to the adequacy of Napier Barracks as asylum-support accommodation under section 95 IAA 1999. Instructed for two of the lead claimants, led by Shu Shin Luh.

Community Care

Antonia specialises in cases that involve a cross-over between community care and immigration. She has particular experience in public law challenges on behalf of age-disputed and unaccompanied asylum-seeking children, including challenges to local authority age assessments and cases that involved detention. In addition, she regularly acts in judicial review challenges under the Children Act 1989, including claims considering the suitability of accommodation and support for age-disputed unaccompanied asylum-seeking children and the provision of section 20 support to children and families.

Significant cases

R (MA & HT) v Secretary of State for the Home Department [2022] EWHC 98 (Admin): Successful challenge to the lawfulness of the Kent Intake Unit social worker guidance governing the conduct of age assessments for putative children while detained at the KIU. 

Birmingham City Council v London Borough of Croydon [2021] EWHC 1990 (Admin) – a challenge brought between local authorities concerning disputed responsibility for Children Act 1989 support and accommodation for a young person "YG". Representing YG as interested party. 

R (ZBR) v Kent County Council [2023] UKAITUR JR2022LON000431 – a complex age dispute challenge on behalf of a young Iranian asylum-seeker whose claim relied substantially on identity documents disputed as being genuine by the local authority. The claim was successful and Kent’s application for permission to appeal to the Court of Appeal refused. 

Public Inquiries

From 2018 to 2022, Antonia was instructed as junior counsel to the independent Inquiry into Child Sexual Abuse, led by Henrietta Hill KC, working on the children outside the UK (Phase 2) and investigation into child sexual exploitation by organised networks investigations. The final report of the inquiry is available here.