A. Whether the applicant was deprived of his liberty 42. It is not disputed by the Government that the applicant's detention at Oakington amounted to a deprivation of liberty within the meaning of Article 5 § 1. The Grand Chamber considers it clear that, given the degree of confinement at Oakington, Mr Saadi was deprived of his liberty within the meaning of Article 5 § 1 during the seven days he was held there (see, for example, Engel and Others v. the Netherlands, judgment of 8 June 1976, Series A no. 22, §§ 60-66).
43. Article 5 § 1 sub-paragraphs (a) to (f) contain an exhaustive list of permissible grounds of deprivation of liberty, and no deprivation of liberty will be lawful unless it falls within one of those grounds (see, inter alia, Witold Litwa v. Poland, no. 26629/95, § 49, ECHR 2000-III). In the present case the Government',s principal contention is that the detention was justified under the first limb of Article 5 § 1(f); although they argue in the alternative that it might also have been justified under the second limb of that sub-paragraph. The Court must accordingly first ascertain whether the applicant was lawfully detained "to prevent his effecting an unauthorised entry into the country".
B. Whether the deprivation of liberty was permissible under subparagraph (f) of Article 5 § 1
a) The meaning of the phrase "... to prevent his effecting an unauthorised entry into the country" 61. In the present case the Court is called upon for the first time to interpret the meaning of the words in the first limb of Article 5 § 1(f), "... lawful ... detention of a person to prevent his effecting an unauthorised entry into the country ..." (in French: "la détention [régulière] d'une personne pour l'empêcher de pénétrer irrégulièrement dans le territoire"). In ascertaining the Convention meaning of this phrase, it will, as always, be guided by Articles 31 to 33 of the Vienna Convention on the Law of Treaties (paragraphs 26-28 above, and see, for example, Golder v. the United Kingdom, judgment of 21 February 1975, Series A no. 18, § 29; Johnston and Others v. Ireland, judgment of 18 December 1986, Series A no. 112, § 51 et seq.; Lithgow and Others v. the United Kingdom, judgment of 8 July 1986, Series A no. 102, §§ 114 and 17; Witold Litwa v. Poland, cited above, §§ 57-59).
63. When considering the object and purpose of the provision within its context, and the international law background, the Court has regard to the importance of Article 5 in the Convention system: it enshrines a fundamental human right, namely the protection of the individual against arbitrary interferences by the State with his right to liberty (see, inter alia, Winterwerp v. the Netherlands, judgment of 24 October 1979, Series A no. 33, § 37 and Brogan and Others v. the United Kingdom, judgment of 29 November 1988, Series A no. 145-B, § 58).
64. Whilst the general rule set out in Article 5 § 1 is that everyone has the right to liberty, Article 5 § 1(f) provides an exception to that general rule, permitting States to control the liberty of aliens in an immigration context. As the Court has remarked before, subject to their obligations under the Convention, States enjoy an "undeniable sovereign right to control aliens' entry into and residence in their territory" (see the Amuur judgment cited above, § 41; the Chahal judgment cited above, § 73; Abdulaziz, Cabales and Balkandali v. the United Kingdom, judgment of 28 May 1985, Series A no. 94, §§ 67-68). It is a necessary adjunct to this right that States are permitted to detain would-be immigrants who have applied for permission to enter, whether by way of asylum or not. It is evident from the tenor of the judgment in Amuur that the detention of potential immigrants, including asylum seekers, is capable of being compatible with Article 5 § 1(f).
65. On this point, the Grand Chamber agrees with the Court of Appeal, the House of Lords and the Chamber, that until a State has "authorised" entry to the country, any entry is "unauthorised" and the detention of a person who wishes to effect entry and who needs but does not yet have authorisation to do so, can be, without any distortion of language, to "prevent his effecting an unauthorised entry". It does not accept that, as soon as an asylum seeker has surrendered himself to the immigration authorities, he is seeking to effect an "authorised" entry, with the result that detention cannot be justified under the first limb of Article 5 § 1 (f). To interpret the first limb of Article 5 § 1(f) as permitting detention only of a person who is shown to be trying to evade entry restrictions would be to place too narrow a construction on the terms of the provision and on the power of the State to exercise its undeniable right of control referred to above. Such an interpretation would, moreover, be inconsistent with Conclusion No. 44 of the Executive Committee of the United Nations High Commissioner for Refugees' Programme, the UNHCR's Guidelines and the Committee of Ministers' Recommendation (see paragraphs 34-35 and 37 above), all of which envisage the detention of asylum seekers in certain circumstances, for example while identity checks are taking place or when elements on which the asylum claim is based have to be determined.
66. While holding, however, that the first limb of Article 5 § 1(f) permits the detention of an asylum seeker or other immigrant prior to the State's grant of authorisation to enter, the Court emphasises that such detention must be compatible with the overall purpose of Article 5, which is to safeguard the right to liberty and ensure that no-one should be dispossessed of his or her liberty in an arbitrary fashion.
The Court must now consider what is meant by "freedom from arbitrariness" in the context of the first limb of Article 5 § 1(f) and whether, in all the circumstances, the applicant's detention was compatible with that provision.
b) The notion of arbitrary detention in the context of Article 5
67. It is well established in the Court's case-law under the subparagraphs of Article 5 § 1 that any deprivation of liberty must, in addition to falling within one of the exceptions set out in sub-paragraphs (a)-(f), be "lawful". Where the "lawfulness" of detention is in issue, including the question whether "a procedure prescribed by law" has been followed, the Convention refers essentially to national law and lays down the obligation to conform to the substantive and procedural rules of national law. Compliance with national law is not, however, sufficient: Article 5 § 1 requires in addition that any deprivation of liberty should be in keeping with the purpose of protecting the individual from arbitrariness (see, among many other authorities, Winterwerp, cited above § 37; Amuur, cited above, § 50; Chahal, cited above, § 118, and Witold Litwa, cited above, § 78). It is a fundamental principle that no detention which is arbitrary can be compatible with Article 5 § 1 and the notion of "arbitrariness" in Article 5 § 1 extends beyond lack of conformity with national law, so that a deprivation of liberty may be lawful in terms of domestic law but still arbitrary and thus contrary to the Convention.
68. While the Court has not previously formulated a global definition as to what types of conduct on the part of the authorities might constitute "arbitrariness" for the purposes of Article 5 § 1, key principles have been developed on a case-by-case basis. It is moreover clear from the case-law that the notion of arbitrariness in the context of Article 5 varies to a certain extent depending on the type of detention involved (see further below).
69. One general principle established in the case-law is that detention will be "arbitrary" where, despite complying with the letter of national law, there has been an element of bad faith or deception on the part of the authorities (see, for example, Bozano v. France, judgment of 18 December 1986, Series A no. 111; Čonka v. Belgium, no. 51564/99, ECHR 2002-I). The condition that there be no arbitrariness further demands that both the order to detain and the execution of the detention must genuinely conform with the purpose of the restrictions permitted by the relevant sub-paragraph of Article 5 § 1 (Winterwerp, cited above, § 39; Bouamar v. Belgium, judgment of 29 February 1988, Series A no. 129, § 50; O'Hara v. the United Kingdom, no. 37555/97, § 34, ECHR 2001-X). There must in addition be some relationship between the ground of permitted deprivation of liberty relied on and the place and conditions of detention (see the abovementioned Bouamar judgment, § 50; Aerts v. Belgium, judgment of 30 July 1998, Reports 1998-V, § 46; Enhorn v. Sweden, no. 56529/00, § 42, ECHR 2005-I).
70. The notion of arbitrariness in the contexts of sub-paragraphs (b), (d) and (e) also includes an assessment whether detention was necessary to achieve the stated aim. The detention of an individual is such a serious measure that it is justified only as a last resort where other, less severe measures have been considered and found to be insufficient to safeguard the individual or public interest which might require that the person concerned be detained (see Witold Litwa, cited above, § 78; Hilda Hafsteinsdóttir v. Iceland, no. 40905/98, § 51, 8 June 2004; Enhorn v. Sweden, cited above, § 44). The principle of proportionality further dictates that where detention is to secure the fulfilment of an obligation provided by law, a balance must be struck between the importance in a democratic society of securing the immediate fulfilment of the obligation in question, and the importance of the right to liberty (see Vasileva v. Denmark, no. 52792/99, § 37, 25 September 2003). The duration of the detention is a relevant factor in striking such a balance (ibid., and see also McVeigh and Others v. the United Kingdom, applications nos. 8022/77, 8025/77, 8027/77, Commission decision of 18 March 1981, DR 25, pp. 37-38 and 42).
71. The Court applies a different approach towards the principle that there should be no arbitrariness in cases of detention under Article 5 § 1(a), where, in the absence of bad faith or one of the other grounds set out in paragraph 69 above, as long as the detention follows and has a sufficient causal connection with a lawful conviction, the decision to impose a sentence of detention and the length of that sentence are matters for the national authorities rather than for the Court under Article 5 § 1 (see T. v. the United Kingdom [GC], no. 24724/94, § 103, ECHR 2000-I ; and also Stafford v. the United Kingdom [GC], no. 46295/99, § 64, ECHR 2002-IV). 72. Similarly, where a person has been detained under Article 5 § 1(f), the Grand Chamber, interpreting the second limb of this sub-paragraph, held that, as long as a person was being detained "with a view to deportation", that is, as long as "action [was] being taken with a view to deportation", there was no requirement that the detention be reasonably considered necessary, for example to prevent the person concerned from committing an offence or fleeing (Chahal, cited above, § 112). The Grand Chamber further held in Chahal that the principle of proportionality applied to detention under Article 5 § 1(f) only to the extent that the detention should not continue for an unreasonable length of time; thus, it held (§ 113) that "any deprivation of liberty under Article 5 § 1(f) will be justified only for as long as deportation proceedings are in progress. If such proceedings are not prosecuted with due diligence, the detention will cease to be permissible ..." (and see also Gebremedhin [Gaberamadine] v. France, no. 25389/05, § 74, ECHR 2007-...).
73. With regard to the foregoing, the Court considers that the principle that detention should not be arbitrary must apply to detention under the first limb of Article 5 § 1(f) in the same manner as it applies to detention under the second limb. Since States enjoy the right to control equally an alien's entry into and residence in their country (see the cases cited in paragraph 63 above), it would be artificial to apply a different proportionality test to cases of detention at the point of entry than that which applies to deportation, extradition or expulsion of a person already in the country.
74. To avoid being branded as arbitrary, therefore, such detention must be carried out in good faith; it must be closely connected to the purpose of preventing unauthorised entry of the person to the country; the place and conditions of detention should be appropriate, bearing in mind that "the measure is applicable not to those who have committed criminal offences but to aliens who, often fearing for their lives, have fled from their own country" (see Amuur, § 43); and the length of the detention should not exceed that reasonably required for the purpose pursued.
c) Was the applicant's detention arbitrary?
75. Before examining whether the applicant's detention at Oakington was arbitrary in the sense outlined above, the Court observes that the national courts at three levels found that it had a basis in national law, and the applicant does not contend that this conclusion was incorrect.
76. In examining whether the applicant's detention was compatible with the criteria set out in paragraph 74 above, the Court further recalls the following findings of the Court of Appeal and House of Lords (see paragraphs 17-18 above), which it accepts. The national courts found that the purpose of the Oakington detention regime was to ensure the speedy resolution of some 13,000 of the approximately 84,000 asylum applications made in the United Kingdom per year at that time. In order to achieve this objective it was necessary to schedule up to 150 interviews a day and even small delays might disrupt the entire programme. The applicant was selected for detention on the basis that his case was suited for fast track processing.
77. In these circumstances, the Court finds that the national authorities acted in good faith in detaining the applicant. Indeed the policy behind the creation of the Oakington regime was generally to benefit asylum seekers; as Lord Slynn put it, "getting a speedy decision is in the interests not only of the applicants but of those increasingly in the queue" (see paragraph 18 above). Moreover, since the purpose of the deprivation of liberty was to enable the authorities quickly and efficiently to determine the applicant's claim to asylum, his detention was closely connected to the purpose of preventing unauthorised entry.
78. As regards the third criterion, the place and conditions of detention, the Court notes that the Oakington Centre was specifically adapted to hold asylum seekers and that various facilities, for recreation, religious observance, medical care and, importantly, legal assistance, were provided (see paragraph 25 above). While there was, undoubtedly, an interference with the applicant's liberty and comfort, he makes no complaint regarding the conditions in which he was held and the Court holds that the detention was free from arbitrariness under this head.
79. Finally, as regards the length of the detention, the Court recalls that the applicant was held for seven days at Oakington, and released the day after his claim to asylum had been refused at first instance. This period of detention cannot be said to have exceeded that reasonably required for the purpose pursued.
80. In conclusion, therefore, the Court finds that, given the difficult administrative problems with which the United Kingdom was confronted during the period in question, with an escalating flow of huge numbers of asylum-seekers (and see also Amuur, cited above, § 41), it was not incompatible with Article 5 § 1(f) of the Convention to detain the applicant for seven days in suitable conditions to enable his claim to asylum to be processed speedily. Moreover, regard must be had to the fact that the provision of a more efficient system of determining large numbers of asylum claims rendered unnecessary recourse to a broader and more extensive use of detention powers. It follows that there has been no violation of Article 5 § 1 in the present case.
II. ALLEGED VIOLATION OF ARTICLE 5 § 2 OF THE CONVENTION
81. The applicant contended that he was not informed of the genuine reason for his detention until some 76 hours after his arrest, when the information was given orally to his legal representative in response to that person's enquiry. He alleged a violation of Article 5 § 2 of the Convention, which provides as follows:
"Everyone who is arrested shall be informed promptly, in a language which he understands, of the reasons for his arrest and of any charge against him."
84. The Chamber found a violation of this provision, on the ground that the reason for detention was not given sufficiently "promptly". It found that general statements – such as the parliamentary announcements in the present case – could not replace the need under Article 5 § 2 for the individual to be informed of the reasons for his arrest or detention. The first time the applicant was told of the real reason for his detention was through his representative on 5 January 2001 (see paragraph 14 above), when the applicant had already been in detention for 76 hours. Assuming that the giving of oral reasons to a representative met the requirements of Article 5 § 2 of the Convention, the Chamber found that a delay of 76 hours in providing reasons for detention was not compatible with the requirement of the provision that such reasons should be given "promptly".
85. The Grand Chamber agrees with the Chamber's reasoning and conclusion. It follows that there has been a violation of Article 5 § 2 of the Convention.