The recent Court of Appeal decision of W (Appellant) v H (Respondent) [2016] EWCA Civ 176 has clarified the scope of diplomatic immunity under English law.

The Court of Appeal overturned a first instance decision that a husband (H) could not in principle claim diplomatic immunity in the context of divorce proceedings, ruling that it was not appropriate for the courts to review the underlying basis for the immunity. However, as H was found to be permanently resident in the UK, diplomatic immunity under the applicable international and national law only applied to official acts performed by H in the exercise of his functions. Divorce did not fall within such official acts, and H's appeal was rejected.


W and H were divorced on 17 September 2014. During their marriage, W had lived in the UK. H was a Saudi national and had never sought or been granted any permanent right to remain in the UK. Their marriage broke down in 2012.

On 1 April 2014, H was appointed as "Ambassador and Permanent Representative" of St Lucia to the International Maritime Organisation ("IMO") in the UK.

W brought a claim against H for financial relief under the Matrimonial and Family Proceedings Act 1984. H applied to have the claim struck out on the basis that he had diplomatic immunity.

In these proceedings, the FCO had provided a certificate under Section 8 of the International Organisations Act 1968 (the "1968 Act"), certifying that: (i) the IMO had informed the UK government of H's appointment as Permanent Representative of St Lucia on 8 May 2014, (ii) H's appointment had been notified to the FCO by Santa Lucia, with an arrival date of 14 April 2014 and (iii) the FCO had not been notified that H's diplomatic functions as Permanent Representative had been terminated (the "FCO Certificate").

In a judgment of 8 February 2016, Hayden J ruled at first instance that H was not entitled to immunity, as: (i) his appointment was an "artificial construct" designed to defeat the jurisdiction of the court, and he had not discharged any of his functions as Permanent Representative; and (ii) H was a permanent resident in the UK, meaning that under the relevant law (namely Article 15 of the UK IMO Order (SI 2002/1826), giving effect to the Headquarters Agreement between the UK and the IMO), he enjoyed immunity only in respect of his official functions. H appealed on both grounds.


The Court of Appeal considered first whether H was, in principle, entitled to diplomatic immunity. It then went on to consider whether the diplomatic immunity breached Article 6 of the European Convention on Human Rights (the "ECHR"). Lastly, the Court considered whether H was permanently resident in the UK. The Secretary of State for Foreign and Commonwealth Affairs intervened in the case.

H's entitlement to diplomatic immunity

The Court of Appeal, overturning the ruling on this point at first instance, held that there was no support in international instruments or case law for a functional review by the English courts where there is a challenge to a claim of diplomatic immunity. It observed that:

  • Article VII, Sections 24-25 of the Specialised Agencies Convention provides for specific (and exclusive) mechanisms for dealing with abuses of privileges and immunities. The receiving state can, for example, order the diplomatic representative to leave the country. Moreover, Article V, Section 16 provides that the sending State has a duty to waive immunity in certain circumstances.
  • The Vienna Convention on Diplomatic Relations ("VCDR") also provides for a formal mechanism by which the functions of a diplomat may be brought to an end: either by notification from the sending State to that effect; or by a designation of the diplomat by the receiving State as a persona non grata. Even then, the diplomat will retain his privileges and immunities until he leaves the country or until the expiry of a reasonable period in which to do so.

The Court of Appeal found these provisions to be "fundamentally inconsistent" with any factual inquiry into whether the diplomat had begun to discharge his functions. The Court accepted the submission of the intervening Secretary of State – the decision whether or not to waive the immunity is a matter solely within the executive discretion of the sending State or that State's courts. If the sending State does not waive immunity, the courts of the receiving State are required to grant immunity.

In rejecting the suggestion of a functional inquiry, the Court of Appeal found the approach taken in the case of Al Atiyya v Al Thani [2016] EWHC 212 (QB) to have been correct. In Al Atiyya, Blake J held that English courts treated the question of whether a person is a diplomatic agent as settled by the provision of an FCO certificate indicating that the UK government has accepted that person's accreditation. There would be real difficulties and uncertainties if the courts were to undertake a further inquiry. The control mechanism for abuses of diplomatic immunity is in the hands of the FCO. Otherwise, there was a possibility of conflicting factual findings being made between the court and the FCO, undermining the fundamental principle of international law that the State cannot speak with two voices on such a matter.

Moreover, section 8 of the 1968 Act provides that if a question arises as to a person's entitlement to privilege or immunity, a certificate issued under the authority of the Secretary of State shall be conclusive evidence of that fact. The Court of Appeal held that Hayden J's factual determinations were inconsistent with the "powerful evidence" provided in the FCO Certificate.

Article 6 of the ECHR (right to a fair trial)

Recent case law has highlighted the relationship between the international law of immunity and Article 6 of the ECHR (see our posts on the decisions in Benkharbouche/Janah and Reyes v Al-Malki). The Court of Appeal noted the "clear and consistent" position taken by the courts, that if the immunity reflected generally recognised rules of public international law, it could not be regarded as a disproportionate restriction of the Article 6 right.

The Court of Appeal held that there was a well-established practice of host States granting full diplomatic immunity to Permanent Representatives of international organisations such as the IMO. It ruled accordingly that the immunity reflected international law, or at least the view that it reflected international law was "reasonable and falls within currently accepted international standards".

Permanent residence

Having reached the conclusion that H was entitled to immunity, the Court of Appeal considered whether H's diplomatic immunity was defeated by his permanent residence in the UK. Under the IMO Headquarters Agreement and the UK IMO Order (as well as under Article 38 of the VCDR), a diplomatic agent who is "a national of or permanently resident in" the receiving State will only enjoy immunity in respect of official acts performed in the exercise of his functions.

The Court of Appeal noted that there was no authority from any senior court in the UK on the meaning of "permanently resident", and based its analysis on guidance circulated to all diplomatic missions in London by the UK government in 1969. This guidance established the so-called "but for" test – whether or not, but for the employment with the mission, the diplomat concerned would choose to remain in the receiving State. The Court also noted that other countries had produced similar guidance.

What was required was a "degree of permanence, not a settled intention to reside in the host country until death". On the facts, the Court of Appeal accepted Hayden J's finding that H was a permanent resident in the UK: "there was ample material from which to conclude that H has chosen, over a period of in excess of 35 years and three marriages, to maintain his family base in the UK".


This is an important judgment, providing welcome clarification on the proper scope of diplomatic immunity. This was less than clear following the conflict between the first instance judgment in this case and the judgment in Al Atiyya, identified in our previous blogpost. It rejects the ability of the English courts to undertake a functional review of whether diplomatic immunity is legitimate or an "artificial construct", and underlines the significance of an FCO certificate in this context. The Secretary of State, intervening in the case, highlighted the risk presented by the contrary approach – that the conduct of international relations would be seriously hampered if the accreditation of diplomats was open to scrutiny by national courts.

Accordingly, lawyers and clients will need to bear in mind that whatever the alleged rationale behind the grant of diplomatic immunity by the sending State, and whatever view may be taken of whether diplomatic functions are in fact being performed, the English courts will not look behind that diplomatic immunity where it has been appropriately certified by the Government.

The judgment is also now the leading authority on the meaning of "permanently resident" in the context of diplomatic immunity.