The UN General Assembly adopted the International Covenant on Civil and Political Rights in 1966. It is one of three documents that make up the International Bill of Rights.
The covenant protects many important rights which limit the encroachments of government, including the right to life, freedom of speech, and the right to due process. Unlike the Universal Declaration of Human Rights, the covenant is legally-binding. It is monitored by the United Nations Human Rights Committee, which meets three times per year.
UN Ambassador from the Philippines signing the covenant, 1966 (via UN Photo)