Human rights instruments generally contain two types of rights protecting equal treatment. On the one hand, a prohibition of discrimination in the enjoyment of the rights set out in the respective instrument, such as Article 2 ICCPR , Article 2 ACHPR,  Article 1(1)ACHR , and Article 14 ECHR . The equal treatment provided for in these provisions refers only to the enjoyment of the rights contained in each of the instruments. On the other hand, provisions such as Article 26 ICCPR, Article 3 ACHPR, Article 24 ACHR, and Protocol 12 to the ECHR (as of July 2004 this Protocol had not entered into force) establish a general equality requirement according to which everyone must be treated equally before the law. In other words, it requires that all laws are applied equally to all people under the jurisdiction of the state without discrimination.

Of the supervisory mechanisms examined in this book, the Human Rights Committee is the body which has dealt with the principle of equality and non-discrimination in most detail and the Committee has developed extensive case-law on Article 26. As Article 26 ICCPR is of a free-standing nature, its application is not confined to the rights contained in the Covenant. According to the Human Rights Committee’s General Comment 18: ‘Article 26 provides that all persons are equal before the law and are entitled to equal protection of the law without discrimination, and that the law shall guarantee to all persons equal and effective protections against discrimination on any of the enumerated grounds’.

At the European level, the jurisprudence on the right to equality and non-discrimination is rather limited as the Court has dealt with relatively few discrimination claims. Article 14 ECHR has a narrow scope and the case-law it has generated is both complicated and inconsistent. The main dilemmas that recur in this case-law relate to the accessory nature and the autonomous status of Article 14 ECHR. The European Court addressed these two issues of applicability very early in the operation of the Convention in the case ‘Relating to Certain Aspects of the Laws on the Use of Languages in Education in Belgium   ’ (see below). In this leading case on Article 14, the applicants were a group of French-speaking parents whose children were denied access to the French-language schools in some predominantly Dutch-speaking suburbs of Brussels on the grounds that the French-speaking families did not live in those districts. The Dutch-language schools in the same districts, however, were open to anyone irrespective of his or her place of residence. In finding a violation of Article 2 of Protocol No. 1 (guaranteeing the right to education) in conjunction with Article 14, the Court articulated the following principles (para 9):

While it is true that this guarantee has no independent existence in the sense that under the terms of Article 14 (art. 14) it relates solely to “rights and freedoms set forth in the Convention”, a measure which in itself is in conformity with the requirements of the Article enshrining the right or freedom in question may however infringe this Article when read in conjunction with Article 14 (art. 14) for the reason that it is of a discriminatory nature.

Thus, persons subject to the jurisdiction of a contracting state cannot draw from Article 2 of the Protocol the right to obtain from the public authorities the creation of a particular kind of educational establishment; nevertheless, a state which had set up such an establishment could not, in laying down entrance requirements, take discriminatory measures within the meaning of Article 14 ECHR. These would entail a violation of a guaranteed right or freedom proclaimed by the relevant article read in conjunction with Article 14. It is as though the latter formed an integral part of each of the articles laying down rights and freedoms.

At the Inter-American level, the Inter-American Court has very limited case-law on the topic. Nonetheless, a very important contribution from the Court has come through its advisory opinions. Particularly relevant are Advisory Opinion No. 4 on ‘Proposed Amendments to the Naturalization Provisions of the Political Constitution of Costa Rica’ and Advisory Opinion No. 18 on ‘Juridical Conditions and Rights of the Undocumented Migrants  ’.

At the African level, it is notable that the non-discrimination provision contained in Article 2 ACHPR is the first substantive right listed, appearing before the right to life. In addition, the African Charter  recognises the right to equality in Article 3 and Article 18 proscribes non-discrimination against women, children and the disabled and establishes affirmative action measures in regard to the aged and the disabled.