The right to freedom of speech and expression

This right is vital for many activities relating to the defence of human rights. For example, people have the right to seek, obtain, receive and hold information about human rights and human rights violations. States should ensure that people are able to peacefully protest, publicize and circulate information and criticize the failure of governments to protect or promote human rights.

International standards:

UN Declaration on Human Rights Defenders: Articles 6, 8
Universal Declaration of Human Rights: Article 19
International Covenant on Civil and Political Rights: Article 19
European Convention for the Protection of Human Rights: Article 10

See generally: ‘Why the Fortnum & Mason protesters’ case matters’, New Statesman, 17 November 2011

For anti-fracking protests: