CRC/C/GC/24 detention and confinement called for a global commitment to the abolition of child prisons and large care institutions, alongside scaled-up investment in community-based services (A/HRC/38/36, para. 53). 83. States parties should immediately embark on a process to reduce reliance on detention to a minimum. 84. Nothing in the present general comment should be construed as promoting or supporting the use of deprivation of liberty, but rather as providing correct procedures and conditions in the minority of cases where deprivation of liberty is deemed necessary. Leading principles 85. The leading principles for the use of deprivation of liberty are: (a) the arrest, detention or imprisonment of a child is to be used only in conformity with the law, only as a measure of last resort and for the shortest appropriate period of time; and (b) no child is to be deprived of his or her liberty unlawfully or arbitrarily. Arrest is often the starting point of pretrial detention, and States should ensure that the law places clear obligations on law enforcement officers to apply article 37 in the context of arrest. States should further ensure that children are not held in transportation or in police cells, except as a measure of last resort and for the shortest period of time, and that they are not held with adults, except where that is in their best interests. Mechanisms for swift release to parents or appropriate adults should be prioritized. 86. The Committee notes with concern that, in many countries, children languish in pretrial detention for months or even years, which constitutes a grave violation of article 37 (b) of the Convention. Pretrial detention should not be used except in the most serious cases, and even then only after community placement has been carefully considered. Diversion at the pretrial stage reduces the use of detention, but even where the child is to be tried in the child justice system, non-custodial measures should be carefully targeted to restrict the use of pretrial detention. 87. The law should clearly state the criteria for the use of pretrial detention, which should be primarily for ensuring appearance at the court proceedings and if the child poses an immediate danger to others. If the child is considered a danger (to himself or herself or others) child protection measures should be applied. Pretrial detention should be subject to regular review and its duration limited by law. All actors in the child justice system should prioritize cases of children in pretrial detention. 88. In application of the principle that deprivation of liberty should be imposed for the shortest appropriate period of time, States parties should provide regular opportunities to permit early release from custody, including police custody, into the care of parents or other appropriate adults. There should be discretion to release with or without conditions, such as reporting to an authorized person or place. The payment of monetary bail should not be a requirement, as most children cannot pay and because it discriminates against poor and marginalized families. Furthermore, where bail is set it means that there is a recognition in principle by the court that the child should be released, and other mechanisms can be used to secure attendance. Procedural rights (art. 37 (d)) 89. Every child deprived of his or her liberty has the right to prompt access to legal and other appropriate assistance, as well as the right to challenge the legality of the deprivation of his or her liberty before a court or other competent, independent and impartial authority, and to a prompt decision on any such action. The Committee recommends that no child be deprived of liberty, unless there are genuine public safety or public health concerns, and encourages State parties to fix an age limit below which children may not legally be deprived of their liberty, such as 16 years of age. 90. Every child arrested and deprived of his or her liberty should be brought before a competent authority within 24 hours to examine the legality of the deprivation of liberty or its continuation. The Committee also recommends that States parties ensure that pretrial detention is reviewed regularly with a view to ending it. In cases where conditional release 14