134. Likewise, the Committee has stressed that the child's age and personal maturity must influence the decision about what his/her best interests might be.238 The Commission has considered that the child's level of development and maturity makes it possible for him/her to understand and form his/her own opinion about his/her circumstances and the decisions about the exercise of his/her rights, and therefore these are conditions that are relevant for the degree of influence his/her opinions might have on deciding what must considered to be his/her best interests in the concrete case.239 That is why the child's age and maturity must be duly appraised by the authorities who must adopt any kind of decision in connection with his/her care and well-being.240 iii) Right of the child to personal liberty 135. Article 7.2 of the American Convention provides that “[n]o one shall be deprived of his physical liberty except for the reasons and under the conditions established beforehand by the constitution of the State Party concerned or by a law established pursuant thereto.” 136. As for the Convention on the Rights of the Child, it points out that “[n]o child shall be deprived of his or her liberty unlawfully or arbitrarily" and that, in any case, restrictions on liberty must be carried out "in conformity with the law and shall be used only as a measure of last resort and for the shortest appropriate period of time.”241 137. The Commission has understood that, although it is customary for legislation of states to explicitly stipulate that "protection measures" such as the placement of children in institutions are not tantamount to depriving them of their liberty, in many cases they are subjected to systems that are very similar to the deprivation of liberty or that unnecessarily restrict their right to personal liberty.242 Thus the Principles and Best Practices on the Protection of Persons Deprived of Liberty in the Americas defines what is meant by "deprivation of liberty”: Any form of (...) institutionalization, or custody of a person in a public or private institution which that person is not permitted to leave at will, by order of or under de facto control of a judicial, administrative or other authority (...), for reasons of (...) guardianship (or) protection (...). This category of persons includes (...) persons who are under the custody and supervision of certain institutions such as: (...) institutions for children.243 138. States must establish an open operating system for residential child care centers that enable children to stay in contact with the outside world, participate in social life, and uphold their ties with the their communities and families.244 The IACHR has indicated that institutions that have a closed operating system allowing children restricted contact with their families and communities may constitute a breach of the right to personal liberty.245 238 United Nations Committee on the Rights of the Child, General Comment No. 14, The right of the child to have his or her best interests taken as a primary consideration, May 29, 2013, para. 44: and General Comment No. 12, The right of the child to be heard, July 20, 2009, paras. 82-85. 239 IACHR, The Right of Boys and Girls to a Family. Alternative Care. Ending Institutionalization in the Americas. October 17, 2013, para. 166. 240 IACHR, The Right of Boys and Girls to a Family. Alternative Care. Ending Institutionalization in the Americas. October 17, 2013, para. 166. 241 Article 37.b) of the Convention on the Rights of the Child. IACHR, The Right of Boys and Girls to a Family. Alternative Care. Ending Institutionalization in the Americas. October 17, 2013, para. 582. 242 243Principles and Best Practices on the Protection of Persons Deprived of Liberty in the Americas. General provision. IACHR, The Right of Boys and Girls to a Family. Alternative Care. Ending Institutionalization in the Americas. October 17, 2013, para. 584. 244 245 IACHR, The Right of Boys and Girls to a Family. Alternative Care. Ending Institutionalization in the Americas. October 17, 2013, para. 582. 27