CAT/OP/C/57/4 Annex Compilation of advice provided by the Subcommittee in response to requests from national preventive mechanisms I. Scope of article 4 of the Optional Protocol 1. Article 4 contains two paragraphs that must be read together and that place within the scope of the Optional Protocol any public or private custodial setting under the jurisdiction and control of the State party, in which persons may be deprived of their liberty and are not permitted to leave, either by an order given by any judicial, administrative or other authority or at its instigation or with its consent or acquiescence. 2. The preventive approach underpinning the Optional Protocol means that as extensive an interpretation as possible should be made in order to maximize the preventive impact of the work of the national preventive mechanism. 3. The Subcommittee therefore takes the view that any place in which persons are deprived of their liberty, in the sense of not being free to leave, or in which the Subcommittee considers that persons might be being deprived of their liberty, should fall within the scope of the Optional Protocol, if the deprivation of liberty relates to a situation in which the State either exercises, or might be expected to exercise a regulatory function. In all situations, the national preventive mechanism should also be mindful of the principle of proportionality when determining its priorities and the focus of its work. II. Application of the principle of confidentiality in the work of national preventive mechanisms 4. The Subcommittee has been asked by national preventive mechanisms to clarify the application of the principle of confidentiality in the context of obligations that might be imposed on them to disclose information they obtain in the course of their work. 5. The principle of confidentiality in relation to the work of national preventive mechanisms is outlined in article 21 (2) of the Optional Protocol, which indicates that confidential information collected by national preventive mechanisms shall be privileged, and that no personal data shall be published without the express consent of the person concerned. The Subcommittee believes that the obligation of confidentiality under the Optional Protocol should be given the widest possible interpretation in order to reflect the spirit of the Convention. 6. The role of the national preventive mechanism is to assist in the prevention of torture. It is not an investigative body, and even when the institution performing the functions of the national preventive mechanism, or that is designated as such, has investigative functions or has an obligation to report, when operating as an national preventive mechanism under the Optional Protocol, the preventive nature of its work means that confidentiality should not be breached. 7. Under the Optional Protocol, personal data protection extends to a wide range of persons including, but not limited to, persons deprived of their liberty, their families, lawyers, members of non-governmental organizations and State officials. Personal data shall remain confidential unless the persons concerned have given their express consent for the data to be disclosed. 19