5 Assessing necessity and proportionality EU law prohibits mandatory detention. Therefore, an individual examination is needed when ordering detention. Such examination must assess if deprivation of liberty is necessary and proportionate in the individual case. This test applies to everyone, regardless of age. The difference for children is the parameters used when assessing if deprivation of liberty is arbitrary, in light of the particular vulnerability of children. Protecting the rights of the child requires that the best interests of the child and the impact of detention on the right to respect for family life be carefully assessed before considering depriving a child or their parents of liberty. The assessment must consider the short- and long-term impact of deprivation of liberty on the child, including its possible detrimental effects. This chapter focuses on the third condition illustrated in Figure 8 that must be fulfilled to prevent arbitrary detention. This chapter takes the general framework of assessing necessity and proportionality as a starting point. It first examines the requirement that detention must be a last resort, giving primary consideration to the best interests of the child. The second section is devoted to the right to family life, when children are together with their parents. The third section examines the requirement that detention last only as long as necessary, which is worded more strongly for children, requiring that deprivation of liberty be for the shortest appropriate time. Vulnerable people include children. An additional factor in assessing the proportionality and necessity of detaining them is if the conditions in the detention facility are suitable for the specific needs of the individual and adequate to protect the child from abuse and violence, including from other detainees. Detention of children is arbitrary when conditions are not appropriate. This factor is analysed in more detail in Chapter 6. The best interests of the child play a central role in assessing necessity and proportionality, as illustrated in Figure 9. Figure 8: Five conditions deprivation of liberty must meet to not be unlawful and arbitrary Fundamental rights safeguards Clear legal basis in national law Based on allowed grounds NECESSARY AND PROPORTIONATE Respects procedural safeguards Conditions are humane and dignified Source: FRA, 2017 47