D5 & Ors v Secretary of State for the Home Department

SIAC must apply the same legal approach to appeals against deprivation of British citizenship on any ground that deprivation is conducive to the public good, including serious organised crime and national security. Its task is public-law review of the Secretary of State’s evaluative assessment, not necessarily fact-finding on the balance of probabilities. SIAC must give substantial weight to expert assessments, while ensuring that the decision has a rational evidential basis. The Secretary of State need not make, and SIAC need not make, findings of fact on the balance of probabilities about involvement in serious organised crime. In certified deprivation cases, procedural fairness is secured by the statutory appeal and does not require prior representations.

Four linked appeals arose from decisions involving serious organised crime. D5 and D6 appealed to SIAC against deprivation of British citizenship under section 40(2) of the British Nationality Act 1981. D7 applied to SIAC to review his exclusion from the United Kingdom under section 2C of the Special Immigration Appeals Commission Act 1997. C9 appealed against a certified deprivation decision under section 40(2).

SIAC dismissed the appeals and rejected the applications. The appellants argued that the approach in U3, concerning national-security assessments, did not apply to serious organised crime; that facts had to be established on the balance of probabilities; and that prior representations, proportionality and alternative criminal measures had been required. The central issue was whether the statutory and institutional reasoning in U3 applied to these decisions.

All four appeals were dismissed. Lady Justice Elisabeth Laing gave the judgment, with Lord Justice Green agreeing.

1. Statutory scheme. Sections 40 and 40A of the British Nationality Act 1981 provide no basis for different principles according to the facet of the public good relied on. Parliament entrusted the Secretary of State with a wide discretion to decide whether deprivation is conducive to the public good. The same approach therefore applies to national-security and serious-organised-crime cases.
2. SIAC’s review. The reasoning in U3 v Secretary of State for the Home Department [2025] UKSC 19 transfers persuasively to serious-organised-crime cases. SIAC reviews the Secretary of State’s expert, evaluative assessment on public-law principles. It is not ordinarily deciding a binary factual issue on the balance of probabilities. Institutional competence, democratic accountability, intelligence assessment and the need for precaution require SIAC to attach very considerable weight to the Secretary of State’s evaluation. The decision must nevertheless have an objective and rational evidential basis.
3. The approach does not vary according to whether the assessment concerns past involvement, future risk, or both. In practice, serious-organised-crime assessments commonly address both past conduct and future risk. Section 40(2) does not require the Secretary of State to make findings of fact on the balance of probabilities, and SIAC was not required to make such findings about D5 and D6. The appellants also bore the burden of displacing the decision-maker’s assessment; SIAC’s finding that no reliance could be placed on their denials made any failure to make express findings immaterial.
4. Procedure and alternatives. In a certified section 40(2) case, the statutory appeal to SIAC secures procedural fairness after the decision. There is no right to prior representations. The Secretary of State may wait until a person is outside the United Kingdom where that is necessary to make the disruption effective. The reasoning in U3 about procedure was obiter but strongly persuasive. A serious crime prevention order was not, on these facts, a mandatory relevant consideration: monitoring would be resource-intensive and less effective than exclusion. Criminal prosecution does not prevent the Secretary of State using the statutory power.
5. D7’s application was governed expressly by judicial-review principles under section 2C(3) of the Special Immigration Appeals Commission Act 1997. The same conclusions applied with greater force. SIAC’s decisions disclosed no material public-law error, and all four appeals were dismissed.

• Court of Appeal (Civil Division): In [2025] EWCA Civ 957, dismissed all four appeals.
• Special Immigration Appeals Commission: Dismissed the appeals by D5, D6 and C9 and dismissed D7’s application to review his exclusion decision.