Self-determination

Self-determination expresses the idea that a people should decide its own political future rather than have it imposed by others. It has two faces:

• External self-determination: the choice of international status, including independence, free association or integration with another state.
• Internal self-determination: meaningful participation in government and autonomy within an existing state, including protection of language, culture and institutions.

The principle has driven the largest change in world political organisation of the past century. United Nations membership grew from 51 founding states in 1945 to 193 today, mostly through decolonisation. Yet the same principle generates conflict, because almost every territory contains groups with competing claims to be "the people".

Wilson and Lenin

Woodrow Wilson's Fourteen Points (1918) and Lenin's writings on the right of nations to self-determination gave the idea international prominence at the end of the First World War. In practice the post-war settlements applied it selectively, mainly to the territories of defeated empires.

UN law

The UN Charter (1945) names respect for the principle of equal rights and self-determination of peoples among the purposes of the organisation. General Assembly resolution 1514 (XV) of 1960, the Declaration on the Granting of Independence to Colonial Countries and Peoples, proclaimed that all peoples have the right to self-determination and that colonialism should be brought to a speedy end; it also declared that attempts to disrupt the national unity and territorial integrity of a country are incompatible with the Charter. Common Article 1 of the two 1966 human-rights covenants makes self-determination a treaty right. The 1970 Friendly Relations Declaration lists independence, free association, integration or any other freely determined status as modes of implementing the right.

Remedial secession

Philosophers divide over when secession is justified. Remedial right theories, associated with Allen Buchanan, hold that a group has a right to secede only as a remedy for serious injustice, such as persistent violations of human rights or unjust annexation. Primary right theories hold that groups may secede without prior injustice, either because they are nations (national self-determination) or because a majority in a territory chooses to (plebiscitary or choice theories). Remedial theories fit international practice better; primary theories fit democratic intuitions about consent.

Uti possidetis

International law has generally converted colonial administrative boundaries into international borders (uti possidetis juris), so that "peoples" entitled to external self-determination were defined territorially, not ethnically. This choice limited border wars after decolonisation but left many minorities inside states they did not choose.

• Decolonisation: more than 80 former colonies have become independent since 1945, with the UN Special Committee on Decolonization monitoring remaining non-self-governing territories.
• Quebec: in the 1998 Reference re Secession of Quebec, the Supreme Court of Canada held that neither Canadian constitutional law nor international law gives Quebec a right to secede unilaterally, but that a clear majority on a clear question would create a duty for the federation and provinces to negotiate.
• Kosovo: in its 2010 advisory opinion, the International Court of Justice found that the 2008 declaration of independence did not violate general international law, without deciding whether Kosovo had a right to secede.
• Referendums: South Sudan voted overwhelmingly for independence in January 2011 under a peace agreement and joined the UN that year; Scotland voted to remain in the United Kingdom in an agreed referendum in 2014; Catalonia's 2017 referendum was held against a ruling of Spain's Constitutional Court.
• Chagos: the ICJ's 2019 advisory opinion held that the separation of the Chagos Archipelago from Mauritius before independence breached the right of self-determination.
• Indigenous peoples: the 2007 UN Declaration on the Rights of Indigenous Peoples affirms a right to self-determination exercised mainly through autonomy and self-government.
• Internal autonomy arrangements such as the Åland Islands, South Tyrol and Rojava's self-administration show the range of internal options.

• Who is the "self"? There is no neutral definition of a people; any boundary creates new minorities, and claims can recede indefinitely ("matryoshka" secession).
• Selective application: great powers support self-determination when it suits them and oppose it otherwise, eroding the principle's credibility.
• Violence: contested self-determination claims are among the most common causes of civil war, and partition has often been accompanied by mass displacement.
• Ethnic nationalism: national self-determination can legitimise exclusionary states and homogenising policies.
• Territorial integrity: states and many international lawyers argue that a broad right to secede would destabilise the state system.
• Democratic deficit of uti possidetis: preserving colonial borders privileges arbitrary lines drawn by empires over the wishes of those who live within them.

Self-determination is firmly established as a legal right for colonial peoples and as a principle favouring internal autonomy and participation elsewhere. Outside decolonisation, unilateral secession remains exceptional and rarely recognised. The practical trend in institution design is towards graduated options: federal arrangements, territorial autonomy, consociational power-sharing and negotiated referendums, which give groups voice without forcing an all-or-nothing choice.

• Allen Buchanan and Elizabeth Levinson, "Secession", Stanford Encyclopedia of Philosophy
• General Assembly resolution 1514 (XV) (1960)
• Reference re Secession of Quebec (1998)
• ICJ, Kosovo advisory opinion (2010)
• Allen Buchanan, Secession (Westview Press, 1991)