Greg Ó Ceallaigh KC

Year of Call: 2006 | Year of Silk: 2024

"Greg is fantastic to work with. He has excellent judgement and his advice is always genuinely useful as he quickly gets to the heart of the case and is realistic and pragmatic."

Legal 500, 2024 (Immigration)

"Calm, rational and level-headed. He provides really good advocacy and he is always quick to respond."

Chambers UK, 2024 (Immigration)

"He has a good strategic approach, as well as good drafting skills and analysis."

Chambers UK, 2024 (Immigration)

"He is a really creative, sharp and determined barrister. He is very responsive and collaborative in working with instructing solicitors too."

Chambers UK, 2022 (Immigration)

"Greg has amazing breadth of legal knowledge which he brings to all his cases. He is strategic and quick to develop the right legal arguments and get to the key issues in the case. His oral and written pleadings are superb."

Legal 500, 2021 (Immigration)

"He is very, very effective; he knows exactly how to pitch cases in a way that maximises the chance of success."

Chambers UK, 2021 (Immigration)

Contact

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Greg Ó Ceallaigh KC is a barrister specialising in human rights, asylum and immigration, civil and public law. He is ranked in the Chambers UK Bar Guide 2024 and the Legal 500 2024 for immigration. He is eligible to take work on a Direct Access basis.

Immigration Law

Overview

Greg has over 15 years’ experience in immigration law and has acted in all kinds of matters ranging from the most complex asylum and human rights claims to Tier 1 Investor cases.

He has acted in many of the leading cases on issues such as Third Country cases (including R (SM) v Secretary of State for the Home Department (Dublin Regulation - Italy) [2018] UKUT 429 (IAC) and ZN (Afghanistan) v Secretary of State for the Home Department [2018] EWCA Civ 1059) and immigration detention (such as Fardous v SSHD [2015] EWCA Civ 92,  R(Sathanantham) v SSHD [2016] 4 WLR 128 and R (on the application of) (Hemmati) v Secretary of State for the Home Department [2019] UKSC 56).

He has a particular expertise in human rights (see e.g. R(Ahsan) v SSHD [2018] HRLR 5, Tikka v SSHD [2018] EWCA Civ 642 and QH(Afghanistan) v Secretary of State for the Home Department [2022] EWCA Civ 421) and has acted in the past three test cases on returns to Italy.

The core of Greg's practice is public law challenges to decisions of the Home Office and other bodies dealing with the rights of migrants either in the Administrative Court or the Upper Tribunal, and civil actions to secure compensation where the power of the state has been abused.

Greg is also an extremely experienced Tribunal advocate both at the First-tier and the Upper Tribunal and is regularly instructed in his own right in the Court of Appeal. He has much experience of urgent removal cases and is comfortable taking instructions at short notice.

Greg writes for Macdonald's Immigration Law and Practice and Butterworths Immigration Law Service. He is a regular contributor to Free Movement, and has been featured in national and international press as an expert on immigration issues and the refugee crisis, including the Independent, Wall Street Journal, RTS and Al Jazeera. He is on the Lexisnexis Panel of experts.

Notable Cases

Past notable cases can be viewed below. Click here to see a list of recent notable cases.

QH(Afghanistan) v Secretary of State for the Home Department [2022] EWCA Civ 421

Successful judicial review claim to return unlawfully removed child to the United Kingdom and to obtain damages in respect of his unlawful removal.

 

Begum v Secretary of State for the Home Department [2021] EWCA Civ 1878

Leading case on the definition of Other Family Member for the purposes of the Citizens’ Directive.

 

Tikka v SSHD [2018] EWCA Civ 642
Successfully represented a man whose leave to remain had been revoked following an accident in a case in which the Court gave guidance on the application of the Chikwamba principle.

Ribeli v Entry Clearance Officer, Pretoria [2018] EWCA Civ 611
Acted for the mother of a British citizen seeking to enter the United Kingdom as an Adult Dependent Relative.

Ahsan v SSHD [2018] HRLR 5
Successfully represented the Appellant in a challenge to the certification of his human rights claim in what is the leading case on the application of the principles in Kiarie and Byndloss to the cases of those accused of TOEIC fraud.

R(Tesfay) v SSHD [2016] 1 WLR 4853
Successfully acted for the appellants in the test case on costs in cases where the Secretary of State withdrew the relevant decisions following the Supreme Court's judgment in EM(Eritrea).

SSHD v Vassallo [2016] 2 CMLR 12
Successfully represented an EU national facing deportation having lived in the United Kingdom for 50 years.

R(Sathanantham) v SSHD [2016] 4 WLR 128
Successfully acted for the claimants in a systemic challenge to delays in the provision of accommodation for those released from immigration detention.

Fardous v SSHD [2015] EWCA Civ 931
Successfully defended SSHD appeal of the case of Fardous v SSHD [2014] EWHC 3061 (QBD) in which a Moroccan national won his action for false imprisonment.

Dudaev and Ors v SSHD [2015] EWHC 1641 (Admin)
Case challenging the lawfulness of Sch 3 to the 2004 Act involving the proposed return to Sweden under Dublin procedures of Chechen exiles.

ZS(Afghanistan) v SSHD [2015] EWCA Civ 1137
Test case (heard with Home Office v VS [2015] EWCA Civ 1142) on the application of policies on detention of disputed minors.

MS and others v SSHD [2015] EWHC 1095 (Admin)
Test case challenging lawfulness to Dublin returns to Italy.

R(AMG) v SSHD [2015] EWHC 5 (Admin)
Case challenging the lawfulness of immigration detention of a severe ill man repeatedly detained under the Mental Health Act. Appeal settled by consent.

Tabrizagh and others v SSHD [2014] EWHC 1914 (Admin)
Test case challenging the lawfulness of removals to Italy pursuant to Dublin II.

R (Ismail) v SSHD [2013] EWHC 3921 (Admin)
Successful challenge to the unlawful detention of a Somali national pending a decision to deport and deportation proceedings.

SHL (Afghanistan) v SSHD [2013] UKUT 312 (IAC)
Case involving a trafficked minor and justiciability of the Trafficking Convention, reliance on evidence obtained from a child interviewed when encountered without an appropriate adult, and the relevance of a failure to comply with the SSHD's obligation to trace.

AB (Sudan) v SSHD [2013] EWCA Civ 921
Test case on whether there should be stays on all Dublin II Regulation removals to Italy pending the Supreme Court's consideration of the application for permission to appeal in EM (Eritrea) v SSHD [2012] EWCA Civ 1336 (See also AB (Sudan) v SSHD [2013] EWCA Civ 16 and R (Bushara) v SSHD [2012] EWHC 3483 (Admin)).

R (Paul) v SSHD [2013] EWHC 1317 (Admin)
Challenge to the lawfulness of 30 months' detention with an allegation of non-cooperation, permission having been granted by the Court of Appeal following refusal in the Administrative Court.

Ncube v United Kingdom [2012] ECHR 897
Successful challenge in the European Court of Human Rights to removal in a case of substantial long residence.

R (Cheung) v Secretary of State for the Home Department [2011] EWHC 2337 (Admin)
Challenge to the SSHD's refusal of leave to remain under the seven-year child concession DP 5/96 (settled following grant of permission to the Court of Appeal).

R (Abdullah) v Secretary of State for the Home Department [2010] EWHC 259 (Admin)
Successful challenge, as a junior, to the SSHD's detention of the claimant for three years.

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Administrative and Public Law

Overview

Greg's substantial public law practice primarily involves judicial reviews challenges to decisions affecting the rights of migrants, notably in detention, nationality, accommodation, age assessment and children's rights cases. He has much experience of urgent removal cases and is comfortable taking instructions at short notice.

Greg has significant expertise in immigration detention and has represented detainees in detention claims at every level from the Tribunal to the Supreme Court (such as Fardous v SSHD [2015] EWCA Civ 92, R(Sathanantham) v SSHD [2016] 4 WLR 128 and R (on the application of) (Hemmati) v Secretary of State for the Home Department [2019] UKSC 56), as well as particularly in civil actions for false imprisonment (e.g. Louis v The Home Office [2021] EWHC 288 (QB) and AO v The Home Office [2021] EWHC 1043 (QB)).

Greg is also highly experienced in dealing with costs issues that arise in public law cases (see e.g. R (Tesfay) v SSHD [2016] 1 WLR 4853 and (ZN (Afghanistan) v SSHD [2018] EWCA Civ 1059).

Notable Cases

Past notable cases can be viewed below. Click here to see a list of recent notable cases.

QH(Afghanistan) v Secretary of State for the Home Department [2022] EWCA Civ 421

Successful judicial review claim to return unlawfully removed child to the United Kingdom and to obtain damages in respect of his unlawful removal.

 

ZN(Afghanistan) v SSHD [2018] EWCA Civ 1059
Case dealing with costs in public law cases where a case settles for reasons extraneous to the litigation. The Court gave helpful guidance on the "JFS Principle".

Ahsan v SSHD [2018] HRLR 5
Successfully represented the Appellant in a challenge to the certification of his human rights claim in what is the leading case on the application of the principles in Kiarie and Byndloss to the cases of those accused of TOEIC fraud.

R(Tesfay) v SSHD [2016] 1 WLR 4853
Successfully acted for the appellants in the test case on costs in cases where the Secretary of State withdrew the relevant decisions following the Supreme Court's judgment in EM(Eritrea).

R(CK) v SSHD [2016] Imm AR 894
Leading case establishing the right to challenge decisions made under the Dublin II Regulation on the basis of a breach of human rights or other public law error.

R(Sathanantham) v SSHD [2016] 4 WLR 128
Successfully acted for the claimants in a systemic challenge to delays in the provision of accommodation for those released from immigration detention.

Fardous v SSHD [2015] EWCA Civ 931
Successfully defended SSHD appeal of the case of Fardous v SSHD [2014] EWHC 3061 (QBD) in which a Moroccan national won his action for false imprisonment.

Dudaev and Ors v SSHD [2015] EWHC 1641 (Admin)
Case challenging the lawfulness of Sch 3 to the 2004 Act involving the proposed return to Sweden under Dublin procedures of Chechen exiles.

ZS(Afghanistan) v SSHD [2015] EWCA Civ 1137
Test case (heard with Home Office v VS [2015] EWCA Civ 1142) on the application of policies on detention of disputed minors.

MS and others v SSHD [2015] EWHC 1095 (Admin)
Latest test case challenging lawfulness to Dublin returns to Italy.

R(AMG) v SSHD [2015] EWHC 5 (Admin)
Case challenging the lawfulness of immigration detention of a severe ill man repeatedly detained under the Mental Health Act.

Tabrizagh and others v SSHD [2014] EWHC 1914 (Admin)
Test case challenging the lawfulness of removals to Italy pursuant to Dublin II.

R (Ismail) v SSHD [2013] EWHC 3921 (Admin)
Successful challenge to the unlawful detention of a Somali national pending a decision to deport and deportation proceedings.

AB (Sudan) v SSHD [2013] EWCA Civ 921
Test case on whether there should be stays on all Dublin II Regulation removals to Italy pending the Supreme Court's consideration of the application for permission to appeal in EM (Eritrea) v SSHD [2012] EWCA Civ 1336 (See also AB (Sudan) v SSHD [2013] EWCA Civ 16 and R (Bushara) v SSHD [2012] EWHC 3483 (Admin)).

R (Paul) v SSHD [2013] EWHC 1317 (Admin)
Challenge to the lawfulness of 30 months' detention with an allegation of non-cooperation, permission having been granted by the Court of Appeal following refusal in the Administrative Court.

R (AK) v SSHD [2011] EWHC 3188 (Admin)
Successful challenge to the lawfulness of the detention of a disputed minor (settled following grant of permission).

R (Cheung) v Secretary of State for the Home Department [2011] EWHC 2337 (Admin)
Challenge to the SSHD's refusal of leave to remain under the seven-year child concession DP 5/96 (settled following grant of permission to the Court of Appeal).

R (Abdullah) v Secretary of State for the Home Department [2010] EWHC 259 (Admin)
Successful challenge, as a junior, to the SSHD's detention of the claimant for three years.

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Immigration Detention Civil Claims

Overview

Greg is highly experienced in immigration detention work and has represented detainees in detention claims at every level from the Administrative Court to the Supreme Court (including Fardous v SSHD [2015] EWCA Civ 92, R(Sathanantham) v SSHD [2016] 4 WLR 128 and R (on the application of) (Hemmati) v Secretary of State for the Home Department [2019] UKSC 56), as well as in civil actions for false imprisonment both in the County Court and the Queen's Bench Division ((e.g. Louis v The Home Office [2021] EWHC 288 (QB) and AO v The Home Office [2021] EWHC 1043 (QB))).

He frequently appears pro bono on behalf of Bail for Immigration Detainees. He has contributed to several of the leading practitioners' texts on the subject of immigration detention and is a Lexisnexis Panel expert on false imprisonment.

Notable Cases

Past notable cases can be viewed below. Click here to see a list of recent notable cases.

Jasseh v Home Office [2024] EWHC 31 (KB)
Successfully acted for claimant, a Gambian national who had been unlawfully detained on two separate occasions, for a total of 267 days, with substantial and aggravated damages awarded for breach of Hardial Singh principles. See news item.

Louis v The Home Office [2021] EWHC 288 (QB)

Successful civil action in respect of a person who was detained pending removal to the DRC having arrived in the United Kingdom as a child and been taken into care. The Court found a period of detention of more than three years to have been unlawful.

 

AO v The Home Office [2021] EWHC 1043 (QB)

Successful civil action in respect of a mentally ill Foreign National Offender who was detained for an extended period. The claim succeeded on the basis of Hardial Singh, Article 5 ECHR and a series of Lumba errors including failure to determine an application for accommodation within a reasonable time, and failure to consider a Case Progression Panel’s decision.

 

R(Sathanantham) v SSHD [2016] 4 WLR 128
Successfully acted for the claimants in a systemic challenge to delays in the provision of accommodation for those released from immigration detention.

Kamal v Home Office [2016] EWHC 65 (QB)
False imprisonment trial in respect of an Iraqi Kurd who had been removed to the KRG.

R(MMM) v SSHD [2016] EWHC 2655 (Admin)
Successful challenge to the claimant's detention for the purposes of third country removal.

R(Abdulkadir) v SSHD [2016] EWHC 1504 (Admin)
Challenge to removal to Austria and to the lawfulness of detention pursuant to the Dublin III Regulation.

Fardous v SSHD [2015] EWCA Civ 931
Successfully defended SSHD appeal of the case of Fardous v SSHD [2014] EWHC 3061 (QBD) in which a Moroccan national won his action for false imprisonment.

ZS(Afghanistan) v SSHD [2015] EWCA Civ 1137
Test case (heard with Home Office v VS [2015] EWCA Civ 1142) on the application of policies on detention of disputed minors.

R(AMG) v SSHD [2015] EWHC 5 (Admin)
Case challenging the lawfulness of immigration detention of a severe ill man repeatedly detained under the Mental Health Act. Appeal settled by consent.

R (Ismail) v SSHD [2013] EWHC 3921 (Admin)
Successful challenge to the unlawful detention of a Somali national pending a decision to deport and deportation proceedings.

R (Paul) v SSHD [2013] EWHC 1317 (Admin)
Challenge to the lawfulness of 30 months' detention with an allegation of non-cooperation, permission having been granted by the Court of Appeal following refusal in the Administrative Court.

R (Abdullah) v Secretary of State for the Home Department [2010] EWHC 259 (Admin)
Successful challenge, as a junior, to the SSHD's detention of the claimant for three years.

Contact Greg

Youth Justice & Child Rights

Greg has extensive experience of representing children and disputed minors for more than a decade across public law, immigration and in the context of civil actions. 

He has represented victims of trafficking and has particular experience of helping children who are overseas and are seeking to be reunited with family members, or children seeking to avoid being separated from family members currently in the United Kingdom.

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Education Law

Greg has a particular interest in education law and has successfully acted in both SEND Tribunal cases and judicial review claims.

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Pro Bono Work

Greg undertakes a large volume of pro bono work in immigration law, including for Bail for Immigration Detainees.

Greg was a runner-up at the Bar Pro Bono Award 2009 with a team from Tooks Chambers for work on an application to the Human Rights Appeal Panel in Kosovo on behalf of the family of Mon Balaj.

Greg previously worked on a team writing the legal arguments for an amicus curiae on behalf of Binyam Mohammed (detained at the time in Guantanamo Bay), in Hamdan v Rumsfeld in the United States Supreme Court.

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Notable Cases & News

Joanne Cecil and Greg Ó Ceallaigh to be appointed King’s Counsel

Garden Court Chambers is delighted to announce that Joanne Cecil and Greg Ó Ceallaigh will be appointed King’s Counsel in 2024.

19 January 2024

High Court finds detention to be unlawful with substantial and aggravated damages awarded for breach of Hardial Singh principles

The Claimant was represented by Greg Ó Ceallaigh of the Garden Court Chambers Civil Liberties Team and Irène Nembhard of Birnberg Peirce.

12 January 2024

Court of Appeal rules unlawfully removed child entitled to damages

Our Sonali Naik QC and Greg Ó Ceallaigh of Garden Court Chambers represented the Appellant, instructed by Hannah Baynes of Duncan Lewis.

1 April 2022

Garden Court Immigration Team dedicate 10th Edition of Macdonald's Immigration Law & Practice to the life and legacy of Ian Macdonald QC

The General Editors, Stephanie Harrison QC, Ronan Toal & Sadat Sayeed, are leaders in the field & practice in the number one ranked Garden Court Immigration Team. David Neale is a legal researcher & former barrister

25 June 2021

High Court finds detention to be unlawful with substantial damages awarded for breach of policy and Hardial Singh principles

The Claimant was represented by Greg Ó Ceallaigh of the Garden Court Chambers Civil Liberties Team and Stephanie Hill of Leigh Day.

30 April 2021

Successful TOEIC appellants to be granted 2.5 years Leave to Remain

The client was represented by Greg Ó Ceallaigh of the Garden Court Chambers Immigration Team, instructed by Roberta Haslam & Theodora Middleton of Bindmans LLP.

4 August 2020

Supreme Court holds that Dublin III Detention between January 2014 and March 2017 was unlawful

Irena Sabic of Garden Court was instructed by Bahar Ata of Duncan Lewis; Greg Ó Ceallaigh of Garden Court was instructed by Krisha Prathepan of Duncan Lewis and Raza Halim of Garden Court was instructed by Kaweh Beheshtizadeh of Fadiga and Co.

27 November 2019

Dublin returns to Italy give rise to an arguable breach of article 3 ECHR

Greg Ó Ceallaigh acts for the lead claimant in the successful challenge to the lawfulness of removals to Italy.

4 December 2018

Upper Tribunal rules Home Office’s removal of disputed minor to Germany unlawful and orders his return to UK

QH is represented by Sonali Naik QC and Greg Ó Ceallaigh of the Garden Court Chambers Immigration Team.

4 December 2018

Court of Appeal - detention of asylum seekers unlawful under Article 28 Dublin III

In a majority decision, the Court of Appeal (Etherton and Peter Jackson LLJ; Sales LJ dissenting) delivered a significant judgment affecting the lawfulness of detention of asylum seekers subject to the Dublin III Regulation.

8 October 2018

Court of Appeal overturns decision that Pakistani national married to British woman should return to Pakistan to apply again for entry clearance

Greg Ó Ceallaigh of the Garden Court Chambers Immigration Team was instructed by Liam Doyle at M&K Solicitors. 

29 March 2018

TOEIC litigation—can decisions be challenged from within UK? (Ahsan v The Secretary of State for the Home Department)

Greg Ó Ceallaigh looks at the implications of the important judgment in Ahsan v The Secretary of State

15 January 2018

Migrants accused of cheating in English language test have in-country right of challenge, rules Court of Appeal

Greg Ó Ceallaigh of the Garden Court Chambers Immigration and Public Law Teams represented Ahsan, one of the appellants.

6 December 2017

‘Trafficking is a function of the absence of safe, legal ways to claim asylum in Europe’ - Greg Ó Ceallaigh on Al Jazeera’s Inside Story

Greg Ó Ceallaigh is a member of the Garden Court Chambers Immigration Team.

31 July 2017

What lies ahead for immigration law in 2017?

Greg O Ceallaigh speaks to LexisNexis about what 2017 might mean for immigration law.

24 January 2017

Home Office unlawfully detained victim of torture

The claimant was represented by Greg Ó Ceallaigh of Garden Court's Immigration Detention Team.

4 November 2016

Garden Court and Stephanie Harrison QC shortlisted for Human Rights and Public Law awards

Garden Court has been shortlisted at the Chambers Bar Awards, whilst Stephanie and our Public Law Team are shortlisted at the Legal 500 Awards.

21 October 2016

High Court finds Home Office system for allocating bail accommodation to immigration detainees is operating unlawfully

Stephanie Harrison QC, Anthony Vaughan and Greg Ó Ceallaigh acted for the three successful claimants.

22 July 2016

Court of Appeal rejects attempts by Home Secretary to deport man resident in Britain for 60 years

Stephen Knafler QC and Greg Ó Ceallaigh of Garden Court Chambers represented the respondent, Benedetto Vassallo.

20 January 2016

Court of Appeal rules Home Office acted unlawfully by detaining Iranian child seeking asylum

The child was represented by Stephanie Harrison QC and Shu Shin Luh of Garden Court Chambers.

6 November 2015

Chambers UK Bar Guide ranks Garden Court in Band 1

Garden Court Chambers recognised as a leading set for immigration, social housing, civil liberties, police law, Court of Protection, crime and inquests and public inquiries.

30 October 2015

Court of Appeal upholds finding that Moroccan national was unlawfully detained for eight months

The claimant was represented by Stephanie Harrison QC and Greg Ó Ceallaigh of Garden Court Chambers.

27 August 2015

Court of Appeal to consider Home Office obligations when detaining age disputed children under immigration powers

The Court of Appeal will consider the obligations owed by the Home Office when detaining children who are age disputed. Garden Court Chambers is representing the families.

14 July 2015

Hungary plans 100-mile fence to keep out migrants - Greg Ó Ceallaigh on Al Jazeera's Inside Story

Al Jazeera's Inside Story debates Hungary's plans for a 100-mile fence to keep out migrants. Panellists include Greg Ó Ceallaigh, barrister with the Garden Court Immigration Team.

25 June 2015

UN found to have breached human rights of peaceful protesters

UN to give public apology and compensation for role in deaths of protesters. Paul Troop was leading counsel.

4 March 2015

High Court rules length of Moroccan national's detention unlawful

The High Court has found that the final eight months of a Moroccan national's 22-month immigration detention were unlawful - Mustafa Fardous v SSHD

16 September 2014

High Court releases Somali national and rules detention unlawful

The High Court has ordered the release of a Somali national, ruling his immigration detention unlawful. The man was represented at the trial by Greg Ó Ceallaigh.

16 December 2013

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Background

Greg trained at Garden Court Chambers and Tooks Chambers before becoming a tenant at 1 Pump Court. He re-joined Garden Court Chambers in August 2013.

Before pupillage Greg worked as a researcher for Keir Starmer QC. He was a paralegal at Janes Solicitors while volunteering at the AIRE Centre advising on European law and human rights to members of the public. He assisted in research for Blackstone's Guide to the Identity Cards Act 2006.

Greg has a degree in Philosophy and English from Trinity College Dublin and a Masters' Degree in Legal and Political Theory from University College London. He completed his CPE at City University and BVC at the Inns of Court School of Law.

In 2005 Greg was awarded a Gold Medal for Oratory by the University Philosophical Society of Trinity College Dublin.

In 2006 Greg was awarded the Otto Rix Scholarship by the Honourable Society of the Inner Temple.

Greg considers himself a triathlete based on very limited evidence. He enjoys playing and watching football.

Training and Seminars

Greg regularly provides training in respect of immigration detention and human rights claims.

Education

  • BA (Trinity College Dublin)
  • MA Legal and Political Theory (University College London)
  • CPE (City University)
  • BVC (Inns of Court School of Law)

Languages

  • Irish
  • French (conversational)
  • German (basic)

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