The right to external self-determination—in other words, to unilateral separation from an unwilling parent state and independence or integration into another state—has undergone a dramatic
shift over the last several decades. Previously held to apply only in the context of decolonization, the right is now frequently invoked in a far wider range of territorial disputes. The Friendly Relations Declaration and several other General Assembly resolutions contemplating or authorizing self-determination in cases of “subjection of peoples to alien subjugation, domination, and exploitation,” have endorsed this post-colonial view, and at least one member of the International Court of Justice believes that the Court has “implicitly also adopted this second perspective.” In a well-known formulation of the more expansive conception of the right, the Canadian Supreme Court in Reference Re Secession of Quebec suggested the possibility of external self-determination “where a definable group is denied meaningful access to government to pursue their political, economic, social and cultural development.” In relation to recent conflicts in Kosovo, Crimea, South Ossetia, and elsewhere, international actors have made vastly divergent claims as to what circumstances trigger the right.
Whatever the status under customary international law of a more expansive right to self-determination, the emphasis placed by all sides of the debate on the requisite severity of oppression—colonization, subjugation, or grave denial of human rights—obscures the critical importance of the second necessary element in all formulations of the right to external self determination: the existence of a “people” or “identifiable group” to exercise the right. The practice of states, however, suggests that the characteristics of a group have much more to do with the perceived legitimacy of the exercise of external self-determination than does the nature of the oppressive regime from which independence is sought.
The surprising lack of scholarship on this point may stem from the incorrect assumption that the labels “people” and “identifiable group” as used in the self-determination context are coterminous with their (almost unlimited) other usages. Because the exercise of the right to external self-determination is a territorial act, however, the relevant actor is the entire subset of individuals within a geographically defined area. Thus, the proper question is—or ought to be—whether the entire population within a certain geographical area constitutes an identifiable group eligible for external self-determination.
What, then, constitutes an identifiable group? One part of the answer appears to be a territory’s homogeneity, as evidenced by shared objective characteristics. A panel of experts convened by UNESCO to consider the definition of “a people” in a different context suggested that these objective criteria can include—among others—common historical, ethnic, cultural, linguistic, and religious features. In secession movements that have been recognized as lawful, the seceding territory has typically exhibited a high degree of homogeneity. East Timor, for example, which achieved statehood in 2002 after separating from Indonesia, is approximately 97% Roman Catholic. Iceland, which became fully independent from Denmark in 1944, is made up of approximately 94% Icelanders. Kosovo, which a significant majority of states has recognized as independent since 2008, is 93% ethnic Albanian and 95% Albanian-speaking. By contrast, the territory of North Cyprus—widely considered not to have legally seceded from Cyprus—consists of only 52% Turkish Cypriots. A similar lack of homogeneity (or homogeneity that is not sufficiently distinct from that of the parent state) may be impeding self-determination aspirations in Somaliland, Katanga, Catalonia, Tibet, and elsewhere. These examples, of course, raise more questions than they answer, but a more rigorous survey of demographic statistics and independence movements is beyond the scope of this post.
It would be both harsh and inaccurate to suggest that a territory inhabited by a heterogeneous, pluralistic society is categorically barred from achieving the status of an “identifiable group” and therefore from acquiring the right to external self-determination. Indeed, the United States of 1776 and the South Sudan of 2011 would not have faired well under such a test. The second criterion of “peoplehood” therefore appears to be subjective. Individuals within a given territory, in the words of the UNESCO panel, “as a whole must have the will to be identified as a people or the consciousness of being a people . . . .”
Measuring the subjective cohesiveness of a population is a more difficult undertaking. Still, the modern international community may have recourse to sources more precise than Yeats or Martí for pronouncements of national identity. Informal public opinion polls, referenda, and elections, if representative and fair, can reflect overwhelming consensus on a topic fundamental to the issue of self-determination. In 1971, the International Commission of Jurists found that the results of the 1970 elections in Pakistan, in which 97% of the seats in soon-to-be-Bangladesh went to the pro-independence Awami league, demonstrated that “the population of East Pakistan now considered themselves a people with a natural consciousness of their own and were claiming a high degree of autonomy within the federal state of Pakistan.” Pre-independence referenda—albeit with varying degrees of validity—in South Sudan, Kosovo, Eritrea, and Slovenia reflected similar or greater unanimity and supported the existence of an “identifiable group.”
The ideas presented here do not address whether external self-determination is a legal question to begin with. Nonetheless, the test for an “identifiable group” proposed here provides an alternative framework for understanding the practice of states in relation to self-determination, regardless of whether such practice reflects opinio juris and a more workable legal standard that could alleviate some concerns regarding the appropriateness of legal review. Nor do these ideas illuminate the much-disputed first prong of the external self-determination test. Still, they may serve to reduce the importance of the “oppression prong” by advocating an emphasis on a population’s objective characteristics, which frequently drive oppression in secessionist conflicts and an emphasis on subjective characteristics, which will tend to reflect the occupation, persecution, or deprivations to which that population—now, perhaps, a “people”—has been subjected.
 Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory, Advisory Opinion, Separate Opinion of Judge Higgins, 2004 I.C.J. Rep. 207, ¶¶ 29-30 (9 July).
  2 S.C.R. 217, 287 (Can.).
 Compare, e.g., Accordance with International Law of the Unilateral Declaration of Independence in Respect of Kosovo, Advisory Opinion, Written Statement of Serbia (Apr. 17, 2009), http://www.icj-cij.org/docket/files/141/15642.pdf, with id., Written Statement of The United States (Apr. 17, 2009), http://www.icj-cij.org/docket/files/141/15640.pdf.
 These terms are used interchangeably throughout.
 Sometimes, newly created minority populations (often the majority in the parent state) are entitled to emigrate from the newly independent state into the parent state, but even where legal barriers are absent, many practical obstacles prevent large-scale relocations of this sort.
 Rosalyn Higgins, The Development of International Law Through the Political Organs of the United Nations 104 (1963) (“Self-determination refers to the right of the majority within a generally acceptable political unit to the exercise of power”).
 UNESCO, International Meeting of Experts on further study of the concept of the rights of peoples, at 7-8, SHS-89/CONF.602/7 (Feb. 22, 1990), available at http://unesdoc.unesco.org/images/0008/000851/085152eo.pdf.
 With U.N. support, South Sudan seceded from Sudan following a 2011 referendum.
 UNESCO, supra note 6, at 8.
 International Commission of Jurists, The Events in East Pakistan, 1971, at 72 (1971).
 See the discussion in James R. Crawford, The Creation of States in International Law (2007).