Secretary of State for the Home Department v P3 [2021] EWCA Civ 1642 is about how much SIAC should defer to the Home Secretary’s view about national security concerns. The answer is quite a lot, but not too much.

The background to this case is the Supreme Court decision in Begum, which was decided after the SIAC judgment under appeal. In that case, the Supreme Court ruled that when assessing the Home Secretary’s view of the national security risk posed by an appellant, SIAC should apply ordinary public law principles to the decision rather than making its own assessment of the risk.

Deprived of citizenship, refused entry

P3 was born in Iraq but naturalised as British in 2003. He is 53 years old and married with three British children. The Home Secretary served P3 with an order depriving him of his naturalised citizenship while he was out of the UK in 2017, charging him with links to Iranian intelligence. P3 was one of 148 people deprived of their citizenship that year.

Like Begum, P3’s case at SIAC — the Special Immigration Appeals Commission — was an appeal against refusal of entry clearance. He won, so the Home Office went to the Court of Appeal.

In hearing this case the Court of Appeal sat with two former heads of SIAC (Lady Justice Laing and Sir Stephen Irwin). There were lots of issues raised about jurisdiction and the correct tests to be applied for various legal issues, but ultimately the appeal was decided in favour of the Home Secretary. SIAC, the court found, did not clearly express the need to defer to the Secretary of State’s view on national security issues.

Insufficient deference as required by Begum

All three judges agreed that SIAC had gone too far and had not given due deference to the opinion of the Secretary of State, who is, in some ways better placed to make decisions about national security and gives those decisions democratic legitimacy.

Sir Stephen Irwin, with the agreement of Lord Justice Bean, gave guidance on how SIAC should approach its task:

Drawing the threads together, I accept that in approaching the evaluation of the national security assessment of the Secretary of State, SIAC must pay real respect, or great deference, to that assessment. That is the clear impact of Rehman and of the remarks of Lord Reed, strictly obiter dicta but of the highest persuasive authority, in Begum. I agree with Elisabeth Laing LJ that it is not a permissible approach for SIAC simply to substitute its own views on national security. However, it is the function of SIAC to scrutinise all the evidence, OPEN and CLOSED, with a critical and expert intelligence, to test the approach and the evidence bearing on the assessment, both for and against the conclusions of the Secretary of State, and then applying due deference, to decide whether the conclusions of the Secretary of State were reasonable and, adopting the phrase of the Strasbourg Court, conformed with common sense. In doing so, SIAC is bound to show deference at all stages and at all levels, to the assessments of those responsible for making those assessments professionally.

At this point, Sir Stephen drew a helpful distinction between the types of national security question that SIAC might face:

In matters of high policy, that deference will be effectively simply acceptance. At more granular levels, SIAC will ask questions and consider the detailed replies. Experience suggests these questions will be considered thoughtfully, and the answers very frequently persuasive. Proper deference there must be, but it does not amount to a simply supine acceptance of the conclusions advanced by the Secretary of State. I do not understand that to be in any way implied by the decisions in Rehman or Begum.

So “matters of high policy”, which might be whether a particular organisation is a terrorist group, should attract limited scrutiny if any. “Granular detail” about the risk posed by a particular individual should attract much more scrutiny.

Laing LJ, with the support of Sir Stephen, also provided some clarity about the need to consider whether Article 8 of the European Convention on Human Rights is engaged in each specific entry clearance appeal:

The best forum for considering and definitively deciding, in a case like this, whether the deprivation decision engages, or interferes with, an appellant’s article 8 rights, and whether that interference is justified, is the deprivation appeal. However, when, as here, an appellant has applied for entry clearance to pursue his deprivation appeal, SIAC will inevitably have to decide the jurisdiction issue raised by the deprivation appeal in the entry clearance appeal (unless an appellant confines his argument to common law fairness). I will not express a concluded view on the jurisdiction issue. I do not consider that it would be right for me to express such a view. I consider, rather, that, given the errors of law in SIAC’s approach which I have described, that issue should be remitted to SIAC, which is also seised of Appeal 1, for SIAC to reconsider it in the light of this Court’s judgment. It is desirable that SIAC, the specialist court, should reconsider this issue with a full understanding of its implications.

Laing LJ also held that SIAC would need to reconsider its conclusions on the procedural implications of making P3 challenge his citizenship deprivation from outside the UK.

This appeal resolves one question, but leaves many more to be resolved by SIAC, once again with limited guidance on the correct approach. As the court explained, this appeal was expedited and the judgment produced at speed, but nonetheless it seems likely that P3 will end up back before the Court of Appeal after the next SIAC decision.