European legal and policy framework on immigration detention of children 5.3. Shortest appropriate period of time European and international law requires that immigration detention be only as long as necessary. This means that, for example, detention in view of implementing a removal becomes arbitrary where reasonable prospect of removal no longer exists and the person must be immediately released.211 There must be clear and cogent evidence, not just bare assertion, of the necessity in each individual case.212 This safeguard concerns anyone, not only children. For children, this safeguard is even stronger. At the EU  level, Article  11  (2) of the Reception Conditions Directive and Article 17 (1) of the Return Directive provide that detention of children must be for the shortest appropriate period of time. It is in this spirit that the Dublin Regulation contains reduced time limits for submitting and responding to transfer requests when asylum applicants are detained.213 Sometimes a  more stringent approach is taken, by requiring detention to be for not only the shortest appropriate time, but the shortest possible time. This is the approach that, for example, the Dublin Regulation takes. Its preamble mentions that detention “should be as short a period as possible”.214 Similarly, the CPT recommends that when, exceptionally, children are held with their parents in a detention centre, the deprivation of liberty should detention of children be for “the shortest possible period of time”.215 58 5.3.1. Setting maximum time limits for detaining children Neither international nor European human rights law establishes a maximum time for detention of adults or children. Only in 2012, the UNHCR underlined the need to set a maximum detention period in national legislation to guard against arbitrariness.216 Ø The Return Directive is the first binding supranational document providing a maximum length of immigration detention, albeit only for preremoval detention. No equivalent provision is in the Reception Conditions Directive. The rationale for an upper limit is the desire to prevent instances of indefinite detention. It is based on the consideration that, after a certain time has elapsed and the removal has not been implemented, however exceptional the circumstances are, the deprivation of liberty loses its initial purpose and becomes arbitrary. EU  Member States can take different measures to ensure that children are kept in detention for the shortest possible period. This report reviews three options, as illustrated in Figure 12, namely (1) the establishment of maximum time limits for detention of children, (2) ensuring more regular reviews and (3) speeding up the main procedure (e.g. asylum or return procedure) during which a child is detained. The Return Directive has established the upper limit at 18 months. It received strong criticism internationally and from civil society at the time of its adoption.217 The Return Directive provides two ceilings. The first ceiling is set at six months (Article 15 (5)). Pre-removal detention should normally not be extended beyond such a period. In exceptional cases, Article 15 (6) of the directive provides two exceptions in which detention can be extended for a further 12 months (up to 18 months in total), provided that the possibility is set forth in national law and the authorities make all reasonable efforts to carry out the removal. The first exception is when the removal procedure is likely to last longer because the person does not cooperate. The second exception is beyond the person’s influence; it is if the country of return delays issuing the necessary documentation. Further extension is not possible beyond these reasons and these deadlines.218 211 Return Directive, Article 15 (4); CJEU, C-357/09, Said Shamilovich Kadzoev (Huchbarov), 30 November 2009, para. 63; ECtHR, Mikolenko v. Estonia, No. 10664/05, 8 October 2009, para. 68; UN, Report of the Working Group on Arbitrary Detention, 18 January 2010, A/HRC/13/30, para. 64. See also the Opinion by the Working Group in Mustafa Abdi v. United Kingdom of Great Britain and Northern Ireland, Opinion No. 45/2006, A/HRC/7/4/Add.1 at 40. 212 FRA and the ECtHR (2014), Handbook on European law relating to asylum, borders and immigration, Luxembourg, Publications Office, p. 156. 213 Dublin Regulation, Article 28 (3). 214 Recast Dublin Regulation, recital (20). 215 CPT, Factsheet on Immigration detention, CPT/Inf (2017)3, March 2017. 216 UNHCR, Guidelines on the Applicable Criteria and Standards relating to the Detention of Asylum-Seekers and Alternatives to Detention, 2012, Guideline 6. See also UN, Committee on the Protection of the Rights of All Migrant Workers and Members of Their Families, General Comment No. 2 on the rights of migrant workers in an irregular situation and members of their families, 28 August 2013, CMW/C/GC/2, para. 27. 217 See press release of the UN, ‘UN experts express concern about proposed EU Return Directive’, Geneva, 18 July 2008; UNHCR, UNHCR Position on the Proposal for a Directive on Common Standards and Procedures in Member States for Returning Illegally Staying Third-Country Nationals, 16 June 2008, p. 2. See also ECRE and Amnesty International (2008), ‘Returns’ Directive: European Parliament and Member States risk compromising respect for migrants’ rights’, Joint press release, 20 May 2008 as well as the attached letter to European Parliament Members., 218 See CJEU, C-357/09, Said Shamilovich Kadzoev (Huchbarov), 30 November 2009, para. 60.