Fifth, with regard to a possible domestic UK statute, the Court notes (at paras. 10(ii) and 363(iv)) the possibility of adopting legislation which ‘might have taken the form of a bar of specified claims by foreign nationals or have provided for specific authority for HM armed forces to detain in operations overseas. Both of these were accepted before us on behalf of SM to be possibilities. The latter reflects the approach taken by the United States.’ I see nothing problematic in the latter option, and this is in fact what the UK Parliament should proceed to do (while also considering the possibility of enabling extraterritorial derogations from the Convention, that curiously gets little mention in the judgment). The former option, however, is downright perilous, at least as far as Convention claims are concerned. It would be exceptionally difficult to justify discrimination on the basis of nationality in the security detention context (cf. the Belmarsh case; see also here and here). It would also likely be a losing strategy in the long run, especially bearing in mind the number of people with (dual) UK nationality fighting for Isis or other terrorist groups.
Sixth, with regard to extraterritoriality – it is true, as Sean and Aurel note in their post, that the Court expressed some significant reservations with respect to the more expansive approach to the extraterritorial application of the Convention post Al-Skeini (see paras. 8, 93 ff). Those reservations seem to be twofold: first, that inconsistent and that they overruled earlier cases sub silentio without clearly explaining why; and second, that applying human rights in armed conflict poses serious practical difficulties. Both of these concerns are real and valid. But we must also be aware that we would have to work out all of these difficult questions of how human rights apply on the battlefield even in intra-territorial situations – cf. the horrible position Ukraine finds itself in today. As I have argued many times before, the threshold extraterritoriality question should not be used as proxy for avoiding all these tough cases, which need to be looked at and decided on their merits.
I would also note, however, that something very important line database happens in para. 95 of the judgment, where the Court appears to endorse Leggatt J’ view in Al-Saadoon that the personal model of Article 1 ECHR jurisdiction applies whenever a state uses physical force against a person, thus in effect collapsing this personal model. (I have argued in my book (at 207) precisely that the personal model has to collapse that way and cannot be limited non-arbitrarily, but also that this is not necessarily what the Strasbourg Court wanted to do in Al-Skeini). Essentially the Court of Appeal may already have implicitly decided one of the key issues in Al-Saadoon, thus paving the way to applying the ECHR not only to detention, but to kinetic operations as well.
Seventh, I am surprised that the government persisted with some rather dubious arguments on appeal. First there was the manifestly-destined-to-lose Behrami point on how the conduct of UK troops in Afghanistan is not attributable to the UK, but only to the UN. And then, even more weirdly, that because the UK was acting on behalf of the UN it was entitled to rely on UN immunities before domestic courts. Yes, you read that right – the UK government was saying that it was immune from the jurisdiction of its own courts because it was supposedly acting on the UN behalf. That led to a couple of frankly embarrassing passages in the judgment (para. 76ff), when the Court asked the government whether the UN Secretary-General was even aware that the government was invoking UN immunities (he was not), and the Court then ordering the government to notify the S-G. His legal adviser subsequently replied saying (quite correctly) that ISAF was not a UN operation and that its personnel had no UN immunities to invoke. It is simply beyond me why such arguments – especially the immunities one – ever got made, wasting everybody’s time and energy in the process.