A/73/305 organizations which are based on ideas or theories of superiority of one race or group of persons of one colour or ethnic origin, or which attempt to justify or promote racial hatred and discrimination in any form”. It also requires States parties to “undertake to adopt immediate and positive measures designed to eradicate all incitement to, or acts of, such discrimination” and to make punishable by law “all dissemination of ideas based on racial superiority or hatred, incitement to racial discrimination, as well as all acts of violence or incitement to such acts against any race or group of persons of another colour or ethnic origin”. The Committee on the Elimination of Racial Discrimination has recommended concrete guidance for States parties on the adoption of legislation combating racist speech falling under article 4, and the Special Rapporteur encourages States to review general recommendation No. 35 in order to benefit from its concrete guidance. 52. Article 19 of the International Covenant on Civil and Political Rights protects freedom of opinion and expression, which may be restricted only in law and when such restrictions are necessary for respect of the rights or reputations of others a nd the protection of national security or of public order, or of public health or morals. Any restriction on freedom of speech must not only be a matter of necessity, but must be proportionately tailored to achieve the legitimate end that warrants the restriction. 76 Article 20 of the Covenant states specifically that States parties must legally prohibit “advocacy of national, racial or religious hatred that constitutes incitement to discrimination, hostility or violence”. The Human Rights Committee and a number of human rights mechanisms have interpreted this provision as creating a high threshold because the limitation of speech must remain exceptional. 53. Freedom of expression is also enshrined in the International Convention on the Elimination of All Forms of Racial Discrimination. The Committee on the Elimination of Racial Discrimination has reiterated that freedom of expression is integrated into the Convention, and that the Convention contributes to a fuller understanding of the parameters of freedom of expression under international human rights law. For determining what racist expression should be punishable by law, the Committee stresses the importance of context, which includes: (a) the content and form of the speech; (b) the economic, social and political climate; (c) the speaker’s status and position; (d) the reach of the speech; and (e) the objectives of the speech. As discussed above, nationalist populism can have a profound impact on the national context in ways relevant to the assessment of whether offensive expression has crossed the threshold of discrimination established under the Convention. Nationalist populism shapes the climate of national discourse and can convert public political platforms into vehicles for spreading prejudice and intolerance and even inciting discrimination and violence. For this reason, Member States, and even private actors, such as the technology companies that often directly interface with racist and xenophobic content online, must remain vigilant in their identifica tion of racist expression in national climates in which certain groups are openly committed to spreading and enforcing intolerance. The Committee warns that racist speech may sometimes rely on indirect language to disguise its targets or objectives, and ma y rely on coded symbolic communication to achieve its ends. Even “incitement may be express or implied, through actions such as displays of racist symbols or distribution of materials as well as words”. 77 54. Member States must take urgent action to ensure that racist expression violating the standards set out in the International Convention on the Elimination of All Forms of Racial Discrimination are made punishable by law. In this regard, the Committee __________________ 76 77 18/22 See CCPR/C/85/D/1022/2001. Committee on the Elimination of Racial Discrimination, general recommendation No. 35 (2013) on combating racist hate speech, para. 16. 18-12945