B4 v Secretary of State for the Home Department

The Court of Appeal dismissed the appellant's challenge to the Secretary of State's decision to deprive him of British citizenship under section 40(2) of the British Nationality Act 1981. The court applied established public law principles governing relevant considerations (Fewings and the Wednesbury test) and concluded that any meaningful exculpatory material is an "obviously material" consideration which the Secretary of State must take into account. The court held that SIAC was entitled to decide whether the advice presented to the Secretary of State was fair and balanced, applying appropriate deference to expert national security assessments, and that SIAC had in fact applied a searching review (a "powerful microscope" or anxious scrutiny) to the closed and open material. Any error in SIAC's formulation of its task was not material because the outcome would inevitably have been the same.

Background and parties. The appellant, a person born in a non-European country and registered as a British citizen in 2004, was deprived of his British citizenship on 26 October 2018 under section 40(2) of the British Nationality Act 1981 on national security grounds. SIAC (Jay J) dismissed his appeal on 1 November 2022. The appellant appealed to the Court of Appeal with permission on various grounds. The Secretary of State relied on an OPEN ministerial submission summarising Security Service advice and closed material that could not be set out in the OPEN judgment.

Nature of the claim / relief sought. The appellant sought to challenge the lawfulness of the deprivation decision and SIAC's dismissal of his appeal, advancing grounds that SIAC had erred in law in (i) its approach to relevant considerations under section 40, (ii) its treatment of whether the ministerial submission to the Secretary of State was fair and balanced (procedural fairness), (iii) aspects of the closed material and SIAC's application of Wednesbury review to it (CLOSED grounds), and (iv) whether SIAC should have applied "anxious scrutiny"/a heightened standard of review.

Issues framed by the court. The principal issues were (i) whether exculpatory material is an implied mandatory consideration under section 40 or, alternatively, an "obviously material" consideration for Wednesbury review; (ii) whether SIAC misdirected itself in law by treating the fairness of the material presented to the Secretary of State as a Wednesbury question rather than as a matter for SIAC to decide for itself; (iii) whether SIAC erred in relation to the CLOSED material and its approach to review; and (iv) whether SIAC was required to apply "anxious scrutiny".

Court's reasoning and conclusions. The Court of Appeal held that exculpatory material need not be read as an implied statutory mandatory consideration but accepted the Secretary of State's concession that any meaningful exculpatory material is "obviously material" and must be taken into account. The court explained the Fewings/Friends of the Earth framework for relevant considerations and Wednesbury review and confirmed that procedural fairness (the question whether the advice was fair and balanced) is an objective question for the court (or SIAC) to decide, subject to appropriate respect and deference to expert national security judgments. The court found SIAC had applied a sufficiently searching review — describing SIAC's approach as applying a "powerful microscope" — and that the ministerial submission contained the salient points and presented a fair and balanced summary to the Secretary of State. Any mischaracterisation by SIAC of its role did not produce a material error because the decision would inevitably have been the same on the evidence (Simplex principle). The court therefore dismissed the appeal. The CLOSED aspects of some grounds were dealt with in the CLOSED judgment and do not alter the OPEN outcome.

Appeal dismissed. The Court held that (a) exculpatory material, while not necessarily an implied mandatory statutory consideration, is in practice "obviously material" and must be taken into account; (b) SIAC was required to decide whether the advice presented to the Secretary of State was fair and balanced, applying an objective test while giving appropriate respect to national security expertise; (c) SIAC in this case conducted a searching review (the "powerful microscope"), and any error in SIAC’s formulation was not material because the outcome would inevitably have been the same. For these reasons the appeal was dismissed.

Appeal to the Special Immigration Appeals Commission against the Secretary of State's deprivation decision (deprivation decision made 26 October 2018); SIAC dismissed the appeal on 1 November 2022 (judgment by Jay J). Appeal to the Court of Appeal from SIAC (permission given by SIAC and the Court). Court of Appeal decision: [2024] EWCA Civ 900 (31 July 2024).