application causes unjustifiable disadvantages for a certain group, one can suspect discrimination in the legal sense. Those without a legal status often cannot enjoy various social services, for lack of documents to prove their identity or fear of being found by the authorities. Some regard this as a rightful retribution for lack of legal status, but this situation cannot be overlooked from the perspective of international human rights law. In reality, de facto stateless persons often cannot acquire legal status due to their lower economic or social status. Several factors for discrimination such as ethnicity, national origin, or race may intertwine in working against them. Such being the case, one could reasonably suspect that the creation of different categories of non-citizens may have a discriminatory “effect” if not an intention to impair enjoyment of human rights against undocumented migrants based on ethnicity, national origin, race or other social status73. It should be recalled that the Committee on the Elimination of Racial Discrimination indeed asserts that under the International Convention on the Elimination of All Forms of Racial Discrimination, “... differential treatment based on citizenship or immigration status will constitute discrimination if the criteria for such differentiation, judged in the light of objectives and purposes of the Convention, are not applied pursuant to a legitimate aim, and are not proportional to the achievement of this aim.” It goes on to recommend State parties to “ensure that immigration policies do not have the effect of discriminating against persons on the basis of race, colour, descent or national or ethnic origin.”74 The Inter-American Court of Human Rights expressed upon discussing the concept of discrimination in detail in its advisory opinion on the rights of illegal immigrants: “Migratory status of a person cannot constitute a justification to deprive him of the enjoyment and exercise of human rights, including those of a labor-related nature…. The State may not subordinate or condition observance of the principle of equality before the law and non-discrimination to achieving their public policy goals, whatever these maybe, including those of a migratory character.”75 Similarly, the Committee on Economic, Social and Cultural Rights confirms in its 73 Lee, supra note 19, pp.100-101. General Recommendation No.30: Discrimination Against Non Citizens: 01/10/2—4 paras.4, 9. 75 Inter-American Court of Human Rights, Re Judicial Condition and Rights of Undocumented Migrants, Advisory Opinion of 17 September 2003, OC-18/03. para.173. 74 31