Executive summary and FRA opinions interpreted restrictively, according to Article 18 of the ECHR. In practice, immigration detention is sometimes imposed for public order-based reasons. FRA opinion 4 Domestic legislation regulating immigration or asylum should not be used to detain individuals on grounds of public order, thereby circumventing the safeguards established under human rights law for criminal detention. EU  Member States should ensure that grounds for immigration detention established at national level do not extend beyond the exhaustive list of legitimate grounds listed in Article 5 (1) of the ECHR, as well as those permissible under the EU  asylum and return acquis. Detention to secure return is not lawful in the absence of realistic prospects for removal. EU  Member States could consider introducing a  presumption against pre-removal detention for de jure as well as de facto stateless persons, including children. This should be one in cases where it is evident from past experience that the country of former habitual residence will not readmit the person or, for de facto stateless persons, the country of nationality will refuse any cooperation in establishing the citizenship and issuing related travel documents. Given its short- and long-term consequences on children’s development, EU  Member States should not use deprivation of liberty as a means to protect children from exploitation and to mitigate risks of them going missing. These risks should be countered by improving reception conditions (including by assigning specialised support staff on a  24/7 basis); strengthening guardianship systems; and gaining a  better understanding of why children go missing and what can be done to prevent their disappearance. These efforts should be accompanied by effective mechanisms to record when a child goes missing and to follow up when the child is found again, as FRA points out in its Opinion on the impact on fundamental rights of the proposal for a  revised Eurodac Regulation. Assessing necessity and proportionality EU and human rights law prohibit automatic detention; an individual examination is therefore always needed before ordering detention. In practice, detention decisions involving children are not necessarily based on careful, individual assessments of necessity and proportionality, as required by Articles 6 and 52 (1) of the Charter. In addition, they do not always give primary consideration to the best interests of the child. Regarding the length of detention, for all persons and not just children, European and international law require immigration detention to be only as long as necessary and to last for the shortest appropriate period. FRA opinion 5 Where they have not yet done so, EU  Member States should issue simple and practicable instructions to support officers responsible for preparing or issuing detention decisions. These instructions should advise officers on the steps to take to ensure that necessity and proportionality are adequately assessed in each individual case, giving primary consideration to the best interests of the child. EU Member States must take adequate legislative and policy measures to ensure that alternatives to detention are not only available on paper but also used in practice for families and children. In the absence of such measures, national authorities cannot justify the use of detention as a last resort. When deciding whether or not to detain a family with children, EU  Member States should always thoroughly assess the best interests of the child, which means being with the parents in open facilities that enable the family to live with dignity. If they are detained, detention has to take place in facilities adequately equipped to host families, also duly taking into account the length of the deprivation of liberty. EU  Member States that allow immigration detention of children should consider fixing a maximum length of child detention. This should be coupled with regular judicial reviews of the necessity and proportionality of detention, which should be based on an individual assessment of the child’s situation by the competent national child protection authorities. Applying child-specific procedural safeguards To ensure that detention is neither unlawful nor arbitrary and, when imposed, does not limit fundamental rights unduly, European and international law provides a set of procedural safeguards. These include the right to judicial review, access to free legal aid and linguistic assistance. Alongside these general safeguards, child-specific safeguards exist, such as appointing guardians for unaccompanied children, as well as conducting procedures and providing information in a child-friendly manner. 9