In the recent decision of Harb v HRH Prince Abdul Aziz Bin Fahd Bin Abdul Aziz [2015] EWCA Civ 481, the English Court of Appeal (the Court) confirmed that the immunity afforded by the UK State Immunity Act 1978 (the SIA) applies to a head of state who dies in office in the same way as it applies to a head of state who stands down from office during his or her lifetime. In short, if the estate is sued, immunity exists only for official acts, and not private acts, committed before the head of state’s death in office. As noted by the Court of Appeal, the case was not covered directly by authority and appears to have been the first case of its kind to have dealt directly with this question of public international law.


The factual background to the case before the Court is more fully described here. In summary, the case concerned a claim against Prince Abdul Aziz (the Prince) of Saudi Arabia, son of the late King Fahd (the King), in relation to an alleged agreement entered into by the Prince in respect of an obligation by the King to provide financial support to Ms Harb. Ms Harb claimed that she was married in secret to King Fahd in 1968, that he had promised to provide for her financially for the rest of her life, and that the Prince had agreed to honour that promise.

Certain facts were assumed and accepted for the purposes of the Court’s consideration of the claim, including that:

  • any agreement the Prince or the King had with Mrs Harb was a private matter and did not involve the exercise of the King’s official functions
  • at the time of any alleged agreement, the Prince was acting as a conduit for or representative of the King and was entitled to the same immunity from suit as his father was entitled to then, and to which his father’s estate would now be entitled.

The question for the Court was therefore whether, after his death in office, the King’s immunity from suit (and hence the Prince’s immunity from suit) extended to acts of the King of a private nature.

Immunity granted to a Head of State under the UK State Immunity Act 1978

The Court noted that the SIA is intended to provide the sole source of English law on the principles of state immunity applicable to heads of state and former heads of state. Accordingly, the extent of the immunity of the King’s estate depended upon correct construction of s20(1) of the SIA.

Section 20(1) provides that the Diplomatic Privileges Act 1964 shall apply to a sovereign or other head of state as it applies to the head of a diplomatic mission, subject to “any necessary modifications“. The Diplomatic Privileges Act 1964 in turn gives effect to certain provisions of the Vienna Convention on Diplomatic Relations 1961 (Vienna Convention). Article 39 of the Vienna Convention provides that immunity ratione personae (i.e. immunity for private acts) for an ambassador lasts only while he or she is in office, but is extended for a short period to allow the ambassador and his or her family (or just family in the case of the ambassador’s death) to leave and take their belongings with them.

Decision of the English High Court – see our blog post here

The High Court had followed the decision of the House of Lords in R v Bow Street Metropolitan Stipendiary Magistrate, ex parte Pinochet (No. 3) [2000] 1 AC 147 (Pinochet No. 3), the leading English case on state immunity (in which Herbert Smith acted for the government of Chile), which established that a former head of state retained immunity only for official acts.

The High Court found that the principles of state immunity apply to a head of state who dies in office in the same way as they apply to a head of state who stands down from office during their lifetime: both enjoy immunity only in respect of their official acts whilst in office. There was no justification for treating the estate of a head of state who dies in office in a more favourable way than (i) a living former head of state or (ii) the estate of a former head of state who dies after leaving office.

Decision of the Court of Appeal

The Court dismissed the appeal against this judgment brought by the Prince. It upheld the approach of the House of Lords in Pinochet No.3, finding that immunity from suit ceases when a head of state ceases to hold office, save in respect of official acts performed whilst he or she was head of state.

The Court rejected the argument that Pinochet No.3 was not binding because it concerned only the extent of the immunity of a living former head of state in respect of official acts committed whilst they were in office. Unless there was some “logical or practical reason” why the immunity afforded to a deceased head of state should differ from that afforded to those who left office, the same rules should apply.

The Court followed a two stage process in establishing what immunity applies to a former head of state in respect of private acts done whilst head of state: (i) to construe Article 39(2) of the Vienna Convention; and (ii) to test that construction against other sources of customary international law.

There is no distinction in Article 39(2) between the position of a diplomat who ceases to perform his or her function because their term of office has come to an end and the position of one who has died en poste. Thus, in making the “necessary modifications” required by Section 20(1) of the SIA to apply Article 39(2) to heads of state, no distinction should be made between a head of state whose term in office comes to an end and a head of state who dies in office. None of the customary law sources considered by the Court distinguished between the application of immunity according to how the head of state lost office.

The Court concluded that a former head of state has no immunity from suit in respect of private acts and that this rule applies whether the person has ceased to be head of state whilst alive or has done so because he or she has died. It also found that:

  • (i) the estate of a deceased head of state does not personify the state any longer. It would not be an affront to the state if the estate is sued in respect of private acts of the deceased head of state;
  • (ii) the “functional basis” of state immunity did not justify an extension of state immunity to the estate of a deceased head of state. Such extension would lead to a difference in treatment between a head of state whose term of office ends after a period of time and one who holds office until death. This would “produce capricious results” and “make a mockery of the doctrine“; and  
  • (iii) there were no practical considerations which necessitated against a finding that immunity should not apply to the estate of a deceased head of state in respect of private acts.

State immunity and the European Convention on Human Rights (“ECHR”)

Although the appeal of the Prince was therefore dismissed, the Court also gave its view on the arguments that had been raised in connection with the ECHR. On this, the Court followed the decision of the High Court and found that, if it had been satisfied that generally recognised rules of public international law conferred immunity on the estate for the King’s private acts, it would not have been open to the Court to lift that immunity on the grounds that it was a disproportionate interference with Ms Harb’s right of access to the courts guaranteed by Article 6 of the ECHR. In doing so, the Court followed the recent European Court of Human Rights decision of Jones v United Kingdom [2014] ECHR 32 (previously reported on the blog here).


The Court criticised the drafting of section 20(1) (“to call [it] clumsy would be an understatement“), but was nevertheless able to reach a clear conclusion on the question before it. The decision that a former head of state loses immunity ratione personae (i.e. immunity for private acts) on death in office is consistent with the general rationale underlying the grant of immunity from suit to heads of state. The historical function of head of state immunity is to facilitate diplomatic interactions with other states and it is in this sense that a head of state is seen to embody the state they represent. If the practical representative function may no longer be carried out by an individual because they die (and this function will most likely have been taken up by a successor), there is no clear justification for treating their estate differently from someone who loses their office by other means. Immunity from suit is, however, retained for official acts, the rationale being that it is necessary to preserve the integrity of those activities of the state of which he or she was head.

The judgment also shows the willingness of the Court to proceed to judgment on questions such as this notwithstanding the lack of clear facts (and the corresponding need to make a range of assumptions), and that any underlying claim against the King would be time-barred. In reaching this decision, the Court acknowledged that the question was not covered by previous authority or considered in any textbook.

For more information, please contact Andrew Cannon, Partner, Harry Ormsby, Associate, or your usual Herbert Smith Freehills contact.

Andrew Cannon
Andrew Cannon
+33 1 53 57 65 52
Harry Ormsby
Harry Ormsby
+44 20 7466 7509