The research did not uncover specific caselaw on the effect of an individual’s statelessness on the legality of detention. However, the Supreme Court in Walumba Lumba347 has recently clarified the relevance of whether an individual can or is willing to return voluntarily to the application of the Hardial Singh principles. Lord Dyson, with whom the majority of the Justices agreed, delivered the leading judgment. He held: “It is necessary to distinguish between cases where return to the country of origin is possible and those where it is not. Where return is not possible for reasons which are extraneous to the person detained, the fact that he is not willing to return voluntarily cannot be held against him since his refusal has no causal effect.”348 Although not all stateless persons will be unable to leave the UK voluntarily, as stateless persons are more likely than others not to have the right to enter another state, they are more likely to be able to show that return is not possible. However, several participants interviewed for the research were detained for significant periods even after it emerged that their claimed country of origin had either denied or refused to confirm that they were entitled to nationality and would not therefore be admitted.349 The UK Border Agency’s published policy sets out how the power to detain will be exercised. The policy must be followed in the absence of a good reason not to.350 The current policy provides that in considering whether to detain an individual there is a “presumption in favour of temporary admission or release and that, wherever possible, [the UK Border Agency] would use alternatives to detention”.351 It further provides that “[d]etention must be used sparingly, and for the shortest period necessary”.352 The policy requires that “[a]ll relevant factors must be taken into account when considering the need for initial or continued detention”.353 It references a number of factors that may be relevant, but statelessness is not identified as a specific consideration. The factors that are specified that are particularly relevant to the situation of stateless persons are: “What is the likelihood of the person being removed and, if so, after what timescale?” “Is there a previous history of complying with the requirements of immigration control?” (e.g. by applying for a visa, further leave, etc) “What are the person’s ties with the United Kingdom? Are there close relatives (including dependants) here? Does anyone rely on the person for support? If the dependant is a child or vulnerable adult, do they depend heavily on public welfare services for their daily care needs in lieu of support from the detainee? Does the person have a settled address/ employment?” 108 347 Walumba Lumba (previously referred to as WL) (Congo) 1 and 2 (Appellant) v. Secretary of State for the Home Department (Respondent); Kadian Mighty (previously referred to as KM) (Jamaica) (Appellant) v. Secretary of State for the Home Department (Respondent), op. cit. 348 Ibid., paras. 127-8. 349 For example, participants 13, 14, 18, 19 and 26. 350 See, for example, Shepherd Masimba Kambadzi (previously referred to as SK (Zimbabwe)) (FC) (Appellant) v. Secretary of State for the Home Department (Respondent), [2011] UKSC 23, United Kingdom: Supreme Court, 25 March 2011, available at: http://www.unhcr.org/refworld/ docid/4e2d8a782.html para. 36. 351 UK Border Agency Enforcement Instructions and Guidance, Section 55.1.1, available at: www.ukba. homeoffice.gov.uk/sitecontent/documents/policyandlaw/enforcement/detentionandremovals/. 352 Ibid., Section 55.1.3 and see further Section 55.3. 353 Ibid., Section 55.3.1. Mapping statelessness