Mark practices in public and EU law. He was awarded Legal Aid Barrister of the Year at the LALY Awards 2010, the citation identifying “his agility of intellect and encyclopaedic legal knowledge combined with his forensic attention to detail". His specialisations include human rights, asylum and immigration, freedom of expression, and community care. He also conducts civil actions against public authorities, especially for unlawful detention, and is instructed to deal with regulatory issues, public procurement and public contracts, particularly relating to legal services.
He has acted in some of the leading cases in public, EU, asylum, and immigration over the last 18 years. He is experienced in running strategic litigation, including test cases on affecting many thousands of claimants in the UK and the EU. He has acted for national and international NGOs in public interest interventions, and is accustomed to dealing with such interventions from NGOs and public authorities in his own cases.
His work encompasses all levels of domestic courts together with the Court of Justice of the European Union (CJEU) and the European Court of Human Rights. He has appeared as lead advocate before both the Chamber and the Grand Chamber of the CJEU. Cases that he presented to the Grand Chamber include the landmark judgment in NS which held that the UK had no opt out from the European Charter of Fundamental Rights. His public law cases have involved cutting edge issues such as the right to disclosure and cross- examination in judicial review, the approach of the Court in Human Rights Act judicial reviews, and the limits of freedom of expression. Leading cases have included Gaunt which established the ability of individual journalists to challenge Ofcom rulings on free speech grounds, and Limbu, the British Army Gurkha judicial review which led to the Government’s defeat in Parliament over Gurkha rights (he was part of the delegation that subsequently collected the Human Rights Award from Justice and Liberty on behalf of the Gurkha Justice Campaign).
He has addressed conferences and seminars on judicial review, EU law, asylum, immigration, and community care for organisations such as Justice, Legal Action Group (LAG), the Immigration Law Practitioners Association (ILPA), the Centre for European Legal Studies at Cambridge, and the British Institute of International and Comparative Law. He is author of the Best Practice Guide to Asylum and Human Rights Appeals (new print edition, published by LAG, due in 2014). He was one of the longest ever elected members of the Executive of ILPA from 2000 until he stood down in 2012 and currently represents ILPA on the users groups of the Administrative Court and the Upper and First-tier Tribunals (IAC). He has sat on Bar Council working parties and advised the Bar Council on public funding issues.
He is briefed as a leading junior, and regularly appears against silks in the domestic courts and the CJEU. He is at ease working electronically and in dealing with urgent matters. He will act on conditional fee agreements where appropriate.
Chambers and Partners 2014 states: ‘Has a complex caseload in the UK and Europe. Praised by his peers, his practice encompasses the full range of immigration and asylum law, and he is regularly instructed on judicial reviews. Expertise: "He's not afraid to tackle the most complex issues."’
Previous editions said "Solicitors instruct Henderson on complicated EEA cases as he is "absolutely excellent on really difficult, technical cases"" (2013); “true expert” and “an extraordinarily tenacious character and a creative thinker who expects the best of himself” (2012); "commended for his expertise on immigration, asylum, EU law and human rights and has recently been involved in cutting-edge judicial review cases relating to disclosure. Sources admire his "phenomenal preparation" as well as his passion and enthusiasm for his subject." (2011),"hugely passionate public lawyer" (2010), "a master of tactics and strategy" (2007) and "incredibly bright and extremely busy" (2004).
The Legal 500 2013 states he is a 'great tactician'). Previous editions said "Mark Henderson is a 'very skilled' specialist in complex EEA appeal matters" (2012). The 2011 edition cited "his involvement in the landmark EU law case of Saeedi"; "outstanding with encyclopaedic knowledge" (2010); "expert in this field" (2008).
Judicial review and public law are at the core of Mark’s practice. His work has involved cutting edge issues such as the entitlement to disclosure and oral evidence in judicial review, the role of the Court in determining claims under the Human Rights Act, and the application of the EU Charter of Fundamental Rights in the UK. He also deals with the Court’s practice and procedure on the Administrative Court Users Group, where he has represented ILPA for several years. He has most recently been involved in achieving changes to crucial Administrative Court guidance for determining inter partes costs disputes where cases have otherwise settled.
Amongst leading cases is Gaunt which established the standing of individual journalists to judicially review Ofcom under Article 10, even where the broadcasting company accepts the ruling. It also considered the role of the Court when hearing a challenge to Ofcom under the Human Rights Act.
He acted in the domestic courts and the CJEU in NS, the judicial review that established the binding effect of the EU Charter of Fundamental Rights in the UK (contrary to claims from a previous Prime Minister and current Lord Chancellor to have achieved an opt out for the UK). It has wide ramifications for public law.
He acted in the landmark British Army Gurkha judicial review, Limbu in which the claimants won a judgment - having successfully challenged the refusal to disclosure high level policy discussions - that the Government’s refusal to grant Gurkhas equal rights with other foreign veterans was unlawful. When the Government then delayed its response, the claimants returned to the Court and obtained an order enforcing its judgment. That led in turn to the Government’s defeat in the House of Commons, following which the Prime Minister conceded equal treatment with other foreign veterans.
His case of CM considered the role of PII Advocates and Special Advocates in judicial review and Upper Tribunal proceedings. The case of S established that judicial review could be brought against the Government's conduct in other court proceedings. The case considered whether and how a public authority could rely on its duty of candour to disclose the claimant’s confidential information in an unrelated judicial review. It involved a direct challenge to the conduct of the Treasury Solicitor in another case and the Attorney General’s personal explanation of that conduct.
In Khadir, Parliament enacted legislation to deprive the claimant of the judgment that he won in the Administrative Court and he appealed to the House of Lords arguing that retrospective legislation to deprive him of his judgment violated constitutional principles of access to the Court. He also acted in major national security cases in the House of Lords, and in Rudi, the House of Lords considered the effect of the common law principle of equality on a judicial review challenge and its relationship with Article 14.
Access to justice cases have included CMX, a judicial review challenging the handling by the Legal Services Commission, Ministry of Justice, and Home Office of the sudden closure as a result of legal aid cuts of a large national provider of legal services. In the course of successive hearings, it was accepted that there was a duty to arrange and fund continuing representation for all several thousand former clients who were initially to be left without representation.
He won a declaration of incompatibility in Nasseri in relation to a key plank of Government legislation (the first in asylum law). This was ultimately overturned by House of Lords which gave important guidance on the role of the Court on such a challenge.
The case of Ahmed broke new ground in judicial review proceedings with extensive orders for disclosure of UK-Iraqi negotiations and orders for cross-examination of Home Office and FCO officials. The sustained efforts necessary to compel full disclosure from the Home Office led the Court to grant Mr Ahmed's application for indemnity costs against it.
A number of judicial reviews have involved challenges to detention or detention conditions, and he is experienced in applying for bail as interim relief. One case in which he acted as leading junior involved fundamental issue of abuse of power by the Home Secretary through using administrative detention to punish non-co-operation with removal where the CPS had advised that no further criminal charge could be brought, and abuse of power by using solitary confinement as punishment, instead of for security and control purposes.
Mark has acted in many leading asylum and immigration cases since the mid 1990s in the UK and Europe. His work ranges from conducting test cases, sometimes with thousands of claimants depending on the outcome, to advising confidentially on particularly sensitive applications to the Home Office.
He has a deep understanding of immigration law, policy, and practice developed through both his litigation and his work on immigration policy issues since the 1990s, including as one of the longest ever elected members of the Executive of ILPA and as an expert adviser to the Immigration Services Commissioner. The last paper edition of his Best Practice Guide to Asylum and Immigration Appeals was distributed to all immigration practitioners nationally by ILPA and the Immigration Services Commissioner. The current electronic edition, co-authored with Alison Pickup, is published on the EIN. LAG will publish a new hard copy edition in 2014.
Leading cases in the CJEU in which he has acted as lead advocate include his current case of McCarthy, which has now been referred to the Grand Chamber due to its importance. It is a test case about whether the UK’s visa and carriers liability regime is incompatible with EU free movement law and whether its Frontier Protocol to the Lisbon Treaty gives the UK an opt out from elements of free movement law. In another recent case, Onuekwere, the CJEU clarified the effect of imprisonment on the right of EU citizens and their family members to permanent residence in EU Member States, and the rationale for the status of permanent resident. He also presented the landmark case of
NS to the Grand Chamber as well as acting in the domestic courts. It established a duty binding on all Member States to respect fundamental rights in preference to EU principles of mutual trust between Member States when transferring asylum seekers under the EU asylum system. It affects thousands of asylum seekers throughout the EU, and forced changes to the main EU legislation which distributes responsibility for considering asylum claims between Member States.
Cases in the European Court of Human Rights include Bensaid. He acted in the domestic courts and in Strasbourg in this landmark case in which the Strasbourg Court first established that Article 8 could be relied upon extraterritorially based on risks in the receiving country that did not engage Article 3. It was key to the House of Lords finally holding that articles of the ECHR other than Article 3 could be relied upon in this way in an expulsion case. Current cases in Strasbourg include Nasseri which has recently been communicated to the UK on the issue of whether the safeguards for asylum seekers facing removal to EU Member States constitute an effective remedy for the purpose of Article 13. In the course of that litigation in the domestic courts, he won the first declaration of incompatibility under the Human Rights Act in respect of asylum legislation. It was ultimately reversed by the House of Lords in 2009 which held that the Court must reach its own factual decision on every claim but was limited to granting a declaration of incompatibility on the facts.
Recent cases domestically include CM (Zimbabwe) which is now the leading Court of Appeal authority on the disclosure and candour obligations applying to the Home Office and Foreign Office in asylum appeals, including country guidance appeals in the Upper Tribunal. It also gave guidance on whether a Special Advocate or PII Advocate should be appointed to deal with Public Interest Immunity issues in asylum appeals.
Before that, he conducted a series of Zimbabwean test cases in the Upper Tribunal, Administrative Court, and Court of Appeal over several years on which thousands of Zimbabwe refugees depended, and which established., for a substantial period, that Zimbabwean asylum seekers were entitled to refugee status unless they were aligned with the Mugabe regime. Later cases involved extensive disclosure of Government policy on Zimbabwe and internal FCO assessments, including exceptional and extensive disclosure orders made by the Court of Appeal.
He also conducted a series of test cases from 2005 challenging removal of asylum seekers to Greece on the basis that it was unsafe. These largely prevented such removals from 2005 until the Home Secretary agreed in 2010, in the face of an application for general relief, to end removals to Greece under the Dublin system and consider claims substantively. She subsequently accepted that such removals violated Articles 3, ECHR and Article 4 of the EU Charter of Fundamental Rights.
He has been involved in a number of cases in which the Home Office was ordered to take steps in a foreign country to achieve the return to the UK of claimants who had been unlawfully removed. The case of S went further by establishing that the Court could order the return of an asylum seekers despite his removal having been lawful, where subsequent conduct by the Home Office had put him at risk from his own authorities. The case involved the duty of confidentiality to asylum seekers in domestic, EU and international law, and established that disclosure could be prohibited even in other legal proceedings (information had been wrongly disclosed by the Treasury Solicitor in a test case challenging a charter flight removal to Sri Lanka, and had led to allegations against the claimant on the Sri Lankan President’s website).
The British Army Gurkha challenge, Limbu, forced the reversal of the Government's policy of preventing Gurkha veterans settling in the UK and led to large numbers being able to do so. The case was decided by the Administrative Court after the claimants judicially reviewed the Tribunal’s decision that it had no power to order the required disclosure on an immigration appeal.
Cases in the House of Lords have included Adan and Aitsegeur, which established as a matter of international law that the Refugee Convention had a single autonomous meaning that domestic courts were required to ascertain, rather than a range of legitimate interpretations. Other cases involved a challenge to the Home Office’s family amnesty in the House of Lords (Rudi). He has also acted in leading cases in the House of Lords dealing with the rules applying to SIAC appeals. (see under National Security)
He has been involved in numerous cases involving asylum support and destitution including acting for the charity Refugee Action in MK, which established that the Home Office’s policy of failing to provide asylum support pending a subsequent asylum claim was unlawful. (see under Community Care)
He has been involved in numerous significant cases since 1995 dealing with the detention of asylum seekers (see also under Actions Against Public Authorities). These include Ahmed, the lead case about the failed attempt to expel asylum seekers to Baghdad by charter flight in October 2009. They often involve applying for complex disclosure of inter governmental communications in order to expose obstacles and delays in effecting removals. His cases have also led to significant concessions in respect of the rights of asylum and immigration detainees to lawyers and to access the Court prior to removal, and effective intervention for those claiming to be children in age dispute cases.
His cases often involve mental health issues, including whether the continued detention of hunger striking mentally ill detainee breached Article 3. His work with children involves cases relying on duties towards children in immigration cases arising from domestic legislation, EU law, and the UN Convention on the Rights of the Child, and include acting for a 10 year old child who attempted suicide in detention in a case which attracted national attention to the detention of children.
He also acts and advises in sensitive and significant individuals applications and appeals in respect of asylum and immigration claims, including advising on alternative bases for obtaining settlement such as investor and entrepreneur applications. In this regard, he can advise on options to enter and remain in the UK for business, employment, and personal purposes; and on making and supporting applications to the Home Office, including PBS applications and particularly sensitive business and personal visitor applications. He can deal with challenges by way of appeal or judicial review.
He usually works with a solicitor but in appropriate cases, he can advise on a public access basis. He cannot reply directly to correspondence on a public access basis until instructions are accepted by his clerks.
Mark is regularly instructed on business and commercial immigration issues. He is instructed by corporate clients (directly and on behalf of employees) to advise and act in matters ranging from business visits to settlement, including establishment of businesses and employee migration and settlement. He has a particular expertise in EU freedom of movement and rights of establishment and appeared as lead advocate in leading cases free movement cases before the Chamber and Grand Chamber of the Court of Justice of the European Union in Luxembourg.
Mark has long experience of community care challenges to decisions of local authorities and the Home Office, including cases involving vulnerable migrants and asylum seekers. He is experienced in handling urgent cases and conducting emergency applications for interim relief on behalf of vulnerable claimants. He has conducted seminars on the procedures and tactics involved in urgent applications for interim relief. He addressed the LAG Community Care conference on using the right to human dignity in community care cases.
Recent cases include acting as leading junior for a major charity Refugee Action, in their intervention in MK, where it was successfully contended that the risk of Article 3 ill-treatment and breach of EU law meant that the Government's policy on asylum support for subsequent claims was unlawful. Other cases included establishing that asylum support appeals were covered by the fair trial guarantees in Article 6.
Mark is regularly instructed in claims against public authorities, particularly the Home Office. He is very experienced in claiming and seeking damages for unlawful detention and unlawful treatment in detention. He is instructed in both civil claims and judicial reviews. He is familiar with both public and private law procedures and with achieving transfer of cases from the Administrative Court to the QBD.
His early cases established rights in relation to bail and damages in the 1990s. Later cases included the House of Lords’ decision in Khadir which clarified fundamental issues concerning the basis of the statutory power of immigration detention.
He has acted recently as leading junior in major unlawful detention challenges such as Mliswa, which became for some time the lead case determining the lawfulness of the administrative detention of a large number of Foreign National Prisoners (FNPs) from Zimbabwe during the suspension of removals to that country. It was contended that the Home Secretary had misrepresented the basis of that suspension in seeking to maintain detention. The Home Office conceded days before the final hearing and paid substantial damages. Another case in which he acted as lead junior involved important issues of the abuse of the power of administrative detention of an FNP in order to circumvent criminal procedure, and abuse of the power of solitary confinement as punishment, and whether continued detention of a mentally ill detainee who was on hunger strike breached Article 3.
He has also acted in civil claims for damages under the Human Rights Act where administrative actions have interfered with family and private life under Article 8.
Mark is experienced in litigating in both European courts and in using international law in domestic courts.
He is regularly instructed in important and complex EU law cases, both in the domestic courts and the Court of Justice in Luxembourg, where he has presented cases before the Chamber and the Grand Chamber. He is experienced in the procedures for requesting references, negotiating the terms of a reference, and subsequent procedure in the CJEU.
Mark acted for the claimant both in the domestic courts and the CJEU in NS, one of the most important EU law cases of recent years. He presented the case to the Grand Chamber in what was amongst the CJEU’s most complex ever hearings, party due to the exceptional number of interventions from Member States and national and international organisations. It established the binding effect of the EU Charter of Fundamental Rights in the UK. The case was of fundamental importance throughout the EU because it established that Member States’ duties under the Charter override the basic EU principle of mutual trust and recognition between Member States.
He also acted as lead advocate in Onuekwere, where the Court gave guidance on the effect of imprisonment on the rights of EU citizens and their family members to obtain permanent residence in other Member States and considered the rationale for granting permanent residence.
He is appearing again as lead advocate before the Grand Chamber in the case of McCarthy in which a number of Member States have intervened. The CJEU will decide whether UK law breaches key EU free movement principles, and whether the UK has achieved an opt out from free movement provisions via its Frontiers Protocol to the Lisbon Treaty. It again raises important issues about the limits of mutual trust between Member States, and the extent to which the doctrine of abuse of rights can be relied on unilaterally by Member States in the absence of EU agreement.
His cases in Strasbourg include Bensaid, an important case on the territorial scope of the Convention, in which the European Court of Human Rights established for the first time that Article 8 could be engaged by treatment in foreign countries that did not engage Article 3 (and which was a foundation of the leading domestic authority on the territorial scope of the Convention). His domestic cases have also included ground breaking arguments on the extra territorial application of the ECHR.
Cases currently in Strasbourg involve freedom of speech (Gaunt) and whether a declaration of incompatibility is an effective remedy under Article 13 for an Article 3 breach given that a court can only advise Parliament that primary legislation violates human rights, rather than order it to change the law to remedy the breach. (Nasseri).
He acts as lead counsel in another current case, Paulet, which is, in essence, an appeal from the leading English criminal law authority on the entitlement of the Crown to confiscate the wages of people who have been convicted in relation to working illegally. It will determine the compatibility of that practice with the ECHR right to peaceful enjoyment of property (Art 1, Protocol 1).
He regularly deals with international law in domestic courts. Other international work has included acting in a case challenging inadequate implementation of international refugee law and EU asylum law in Gibraltar.
He has acted at the highest level in two of the leading national security appeals. RB (Algeria) involved whether the Special Advocate procedure in terrorism cases in SIAC violated Articles 3 and 6 and common law constitutional principles. He also acted for a coalition of NGOs in the internationally acclaimed case which ruled that evidence obtained through torture was inadmissible even in national security cases, A No. 2.
He also acted as leading junior in the leading case on whether a Special Advocate or PII Advocate should deal with FCO disclosure of closed material in the context of a PII process in a country guidance case (CM (Zimbabwe)).
Mark advises solicitors on costs issues, public funding and regulatory matters, and has represented solicitors at hearings of the Legal Services Commission/ Legal Aid Authority’s dispute resolution panels. He acted in a test case which established the right to ongoing public funding for thousands of claimants who were represented by a national legal services provider which went into administration (CMX).
His recent publications include an article on procedures and tactics in obtaining inter partes costs where a judicial review settles, and he has been at the forefront of efforts to improve procedures for determining IP costs applications in the Administrative Court via its Users Group where he represents ILPA .
Mark has a strong interest in equality and discrimination issues, which arise regularly in his cases, whether under domestic law, EU law, or the ECHR/ Human Rights Act. His case of Rudi in the House of Lords considered whether the common law principle of equality now required a proportionality test. He deals with public sector equality duties in his public law practice. His work beyond litigation has included serving on a Bar Council working party on the implementation of the Bar’s Equality Code.
Court of Justice of the European Union, European Court of Human Rights, and House of Lords/Supreme Court
MA (Hertford College, Oxford)
Administrative Law Bar Association
Bar European Group
Immigration Law Practitioners Association
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