Beetham’s model (22.214.171.124) of legitimacy provides a basis for people to assess their own political system and the behaviour of their politicians, but countries do not exist in isolation – particularly nowadays. External perspectives help to improve the quality of debate and may provide an external measure by which to assess legitimacy at level 2 of Beetham’s model: showing that a country’s governance conforms to “beliefs shared” by other countries.
The Universal Declaration of Human Rights, 1948 (the UDHR, see Appendix 1) was negotiated after the Second World War, to set governance standards and to protect people from politicians who abuse their powers. It was adopted by the UN General Assembly, with 48 countries voting for it and 8 abstentions. The UDHR is not legally binding in international law, except for countries that have placed themselves under the jurisdiction of the International Criminal Court (126.96.36.199), but it has considerable moral authority (188.8.131.52).
Even without incorporation into the law, international human rights are a mechanism for putting pressure on national politicians. Concern about human-rights abuses at the Guantánamo Bay detention centre for terrorists led to international protests which put pressure on the American government to close it.
The UDHR can also act as what Adam Smith referred to as an “impartial spectator” for any country reviewing its governance:
“We endeavour to examine our own conduct as we imagine any other fair and impartial spectator would examine it.”
Instead of people asking themselves why they would submit to principles defined by other countries, they should ask themselves why they would allow their governance to fall short of what others see as best practice. And there is no obvious reason why any government cannot meet most of the requirements of the UDHR – although socio-economic rights depend upon affordability and authoritarian governments don’t comply with Article 21.3 (elections).
A country, or group of countries, can also decide to incorporate some human rights in its own laws (5.4.7). The Charter of Fundamental Rights of the European Union, for example, is binding on EU countries and is a test for new applicants. The American Constitution is another example which offers considerable protection to its citizens; it is enforced by the Supreme Court, which acts as a constraint upon politicians. The decision to embody human rights in national laws is an endorsement of their legitimacy.
 The following countries voted in favour of the Universal Declaration of Human Rights (UDHR): Afghanistan, Argentina, Australia, Belgium, Bolivia, Brazil, Burma, Canada, Chile, China, Colombia, Costa Rica, Cuba, Denmark, the Dominican Republic, Ecuador, Egypt, El Salvador, Ethiopia, France, Greece, Guatemala, Haiti, Iceland, India, Iran, Iraq, Lebanon, Liberia, Luxembourg, Mexico, Netherlands, New Zealand, Nicaragua, Norway, Pakistan, Panama, Paraguay, Peru, Philippines, Thailand, Sweden, Syria, Turkey, United Kingdom, United States, Uruguay and Venezuela. This information was on page 22 of the minutes of the 183rd plenary meeting of the UN, which were available in May 2018 at http://www.un.org/en/ga/search/view_doc.asp?symbol=A/PV.183.
 On 12 January 2012 the Washington Post published an article entitled Protesters condemn Guantánamo Bay on 10th anniversary with march from White House, which referred to “a group of hundreds of human rights activists” as “one of several demonstrations around the world”; it was available in May 2018 at http://www.washingtonpost.com/local/protesters-condemn-guantanamo-bay-on-10th-anniversary-with-march-from-white-house/2012/01/11/gIQAVYIDsP_story.html.
Amartya Sen quotes Smith in chapter 6 of The Idea of Justice when making the argument for countries to take account of views from outside their own borders. Sen makes the distinction between internal legitimacy, as being negotiated, and external legitimacy as being “impartial”, in his quest for “The Idea of Justice”.