General Comment 31 on the International Covenant on Civil and Political Rights, Nature of the General Legal Obligation on States Parties to the Covenant (CCPR/C/21/Rev.1/Add.13)

6. The legal obligation under article 2, paragraph 1, is both negative and positive in nature. States Parties must refrain from violation of the rights recognized by the Covenant, and 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. In no case may the restrictions be applied or invoked in a manner that would impair the essence of a Covenant right.