A national human rights institution (NHRI) is an independent state-based institution with the responsibility to broadly protect and promote human rights in a given country. The growth of such bodies has been encouraged by the Office of the United Nations High Commissioner for Human Rights (OHCHR), which has provided advisory and support services, and facilitated access for NHRIs to the United Nations (UN) treaty bodies and other committees. There are over one hundred such institutions, about two-thirds assessed by peer review as compliant with the United Nations standards set out in the Paris Principles. Compliance with the Principles is the basis for accreditation at the UN, which, uniquely for NHRIs, is not conducted directly by a UN body but by a sub-committee of the Global Alliance of National Human Rights Institutions (GANHRI) called the Sub-Committee on Accreditation. The secretariat to the review process (for initial accreditation, and reaccreditation every five years) is provided by the National Institutions and Regional Mechanisms Section of the OHCHR.
NHRIs can be grouped together into two main categories: human rights commissions and ombudspersons. While most ombudspersons have their powers vested in a single person, human rights commissions are led by multi-member boards, often representative of various societal groups. NHRIs are sometimes set up to deal with specific issues such as discrimination, although the Paris Principles requires they should be bodies with broad responsibilities. Specialised national institutions also exist in many countries to protect the rights of a particular vulnerable group such as ethnic and linguistic minorities, indigenous peoples, children, refugees, persons with disabilities or women.
However, national human rights institutions under the Paris Principles have an explicit and broad human rights mandate that should include both promotion and protection functions. This can include research, documentation and training and education in human rights issues, than the classical ombudsman model which tends to work on handling complaints about administrative deficiencies.