Slingenberg 391 of the applicants’ stay, the excessive duration of that stay and the considerable delays in the domestic examination of the applicants’ asylum claims, as well as the conditions in which the applicants were held during the relevant period’ there was a situation of de facto deprivation of liberty.6 As regards confinement in reception centres that are not transit centres, the case law is different. If these centres are partially open, that is, if migrants can leave the centre into the territory of the host state for a couple of hours a day, the Court, without discussing any other criteria, simply concludes that there is no deprivation of liberty.7 This is only different if migrants need written permission to leave the centre, that can be arbitrarily denied (Nur Ahmed and others v. Ukraine, 2020). So, in a number of cases, applicants complained about the freedom restrictions in the Vial reception centre, located at the Greek island of Chios. In these cases, the applicants were issued with decisions forcing them not to leave the island and to stay in the reception centre. This centre was, however, at a certain point transformed from a closed to a semi-open centre, which meant that the applicants could leave during the day but had to return during the night. The Court merely ruled that ‘à partir de cette dernière date, ils ne faisaient l’objet que d’une simple restriction de mouvement’ and concluded that Article 5 did not apply (J.R. and others v. Greece, 2018: para 86; O.S.A. and others v. Greece, 2019: para 43; Kaak and others v. Greece, 2019: para 89). This approach was repeated after the new formulation of the relevant factors for confinement of migrants in Ilias and Ahmed and Z.A. and others. In the case of Alissa v. Romaine, the applicants (beneficiaries of international protection) were placed in a centre from which they could not leave between 10 pm and 6 am. After referring to the case of Ilias and Ahmed, the Court held that the case had most in common with the case of J.R., and, again, merely observed that this placement ‘était une simple restriction de mouvement’ and no deprivation of liberty within the meaning of Article 5 ECHR (Alissa v. Romaine, 2019). Accordingly, if it is possible to leave the centre during the day, having to return to it every night does not constitute deprivation of liberty, according to the ECtHR. The CJEU seems to adopt a similar concept of detention. In the case of FMS and others (C-924/19 PPU and C-925/19 PPU), the CJEU defined detention as (paras 229-231): an obligation imposed on a third-country national to remain permanently in a transit zone the perimeter of which is restricted and closed, within which that national’s movements are limited and monitored, and which he or she cannot legally leave voluntarily, in any direction whatsoever. Hence, a real possibility to leave the centre, albeit temporarily, is a decisive factor that prevents classification as detention and deprivation of liberty. This seems also to be the opinion of the European Fundamental Rights Agency. In its ‘twelve points for protection-sensitive and fundamental rights-compliant planning and design of initial-reception facilities’ (European Union Agency for Fundamental Rights, 2011) it states that: