A/HRC/27/37 Nos. 16, 27, 29, 34, and 31, findings on individual communications11 and concluding observations;12 regional and national case law;13 and the views of independent experts.14 In its general comment No. 31 on the nature of the general legal obligation on States parties to the Covenant, for example, the Human Rights Committee provides that States parties must refrain from violation of the rights recognized by the Covenant, and that “any restrictions on any of [those] rights must be permissible under the relevant provisions of the Covenant. Where such restrictions are made, States must demonstrate their necessity and only take such measures as are proportionate to the pursuance of legitimate aims in order to ensure continuous and effective protection of Covenant rights.”15 The Committee further underscored that “in no case may the restrictions be applied or invoked in a manner that would impair the essence of a Covenant right.” 23. These authoritative sources point to the overarching principles of legality, necessity and proportionality, the importance of which also was highlighted in many of the contributions received. To begin with, any limitation to privacy rights reflected in article 17 must be provided for by law, and the law must be sufficiently accessible, clear and precise so that an individual may look to the law and ascertain who is authorized to conduct data surveillance and under what circumstances. The limitation must be necessary for reaching a legitimate aim, as well as in proportion to the aim and the least intrusive option available.16 Moreover, the limitation placed on the right (an interference with privacy, for example, for the purposes of protecting national security or the right to life of others) must be shown to have some chance of achieving that goal. The onus is on the authorities seeking to limit the right to show that the limitation is connected to a legitimate aim. Furthermore, any limitation to the right to privacy must not render the essence of the right meaningless and must be consistent with other human rights, including the prohibition of discrimination. Where the limitation does not meet these criteria, the limitation would be unlawful and/or the interference with the right to privacy would be arbitrary. 24. Governments frequently justify digital communications surveillance programmes on the grounds of national security, including the risks posed by terrorism. Several contributions suggested that since digital communications technologies can be, and have been, used by individuals for criminal objectives (including recruitment for and the financing and commission of terrorist acts), the lawful, targeted surveillance of digital communication may constitute a necessary and effective measure for intelligence and/or law enforcement entities when conducted in compliance with international and domestic law. Surveillance on the grounds of national security or for the prevention of terrorism or other crime may be a “legitimate aim” for purposes of an assessment from the viewpoint of article 17 of the Covenant. The degree of interference must, however, be assessed against the necessity of the measure to achieve that aim and the actual benefit it yields towards such a purpose. 25. In assessing the necessity of a measure, the Human Rights Committee, in its general comment No. 27, on article 12 of the International Covenant on Civil and Political Rights, stressed that that “the restrictions must not impair the essence of the right […]; the relation 11 12 13 14 15 16 8 For example, communication No. 903/1999, 2004, Van Hulst v. The Netherlands. CCPR /C/USA/CO/4. For example, European Court of Human Rights, Uzun v. Germany, 2 September 2010, and Weber and Soravia v. Germany, para. 4; and Inter-American Court of Human Rights, Escher v. Brazil, Judgment, 20 November 2009. See A/HRC/13/37 and A/HRC/23/40. See also International Principles on the Application of Human Rights to Communications Surveillance, available from https://en.necessaryandproportionate.org/text. CCPR/C/21/Rev.1/Add. 13, para. 6. CCPR/C/21/Rev.1/Add.9, paras. 11 – 16. See also A/HRC/14/46, annex, practice 20.