The Council of Europe drafted the ECHR in 1950 bringing it into force on 3 September 1953. Originally known as the Convention for the Protection of Human Rights and Fundamental Freedoms, the ECHR is an international treaty and therefore legally binding. It is overseen by the ECtHR.
Article 10 of the ECHR provides for the right to freedom of expression:
Article 10 – Freedom of expression
1. Everyone has the right to freedom of expression. This right shall include freedom to hold opinions and to receive and impart information and ideas without interference by public authority and regardless of frontiers. This article shall not prevent States from requiring the licensing of broadcasting, television or cinema enterprises.
2. The exercise of these freedoms, since it carries with it duties and responsibilities, may be subject to such formalities, conditions, restrictions or penalties as are prescribed by law and are necessary in a democratic society, in the interests of national security, territorial integrity or public safety, for the prevention of disorder or crime, for the protection of health or morals, for the protection of the reputation or rights of others, for preventing the disclosure of information received in confidence, or for maintaining the authority and impartiality of the judiciary.