50 incorporate criteria of this nature, in order not to contravene the absolute prohibition against discrimination, must be based upon objective and reasonable justification, in that they further a legitimate objective, regard being had to the principles which normally prevail in democratic societies, and that the means are reasonable and proportionate to the end sought. Distinctions based upon grounds expressly enumerated in the pertinent provisions of international human rights instruments are subject to an enhanced level of scrutiny (…). 175. Specifically, on the need for scrupulous observance of rights when a person’s association with a group may be the grounds for investigating and prosecuting that person for terrorist crimes, the Commission observed that: This would require, for example, the existence of reasonable grounds connecting a particular group to terrorist activities before an individual’s association with that group might properly provide a basis for investigating him or her for terrorist-related crimes. Even then, the extent to which and the manner in which investigative methods of this nature are undertaken and the resulting information is collected, shared and utilized must be regulated in accordance with the principles of reasonableness and proportionality, taking into account, inter alia, the significance of the objective sought and the degree to which the state’s conduct may interfere with the person or persons concerned. (…)States must therefore remain vigilant in ensuring that their laws and policies are not developed or applied in a manner that encourages or results in discrimination, and that their officials and agents, including military forces, conduct themselves fully in conformity with these 194 rules and principles.” 176. Summarizing, under international law, indigenous persons and peoples are titulaires of the right to equality, the right to be free from any form of racial discrimination –particularly any form of racial discrimination based on one’s ethnic origin-, and the right to equal protection by the courts without their ethnicity becoming a cause for distinction, exclusion, restriction or unfavorable bias. These rights take on a specific added meaning in the case of indigenous persons. Article 2 of the United Nations Declaration on the Rights of Indigenous :Peoples provides that "[i]ndigenous peoples and individuals are free and equal to all other peoples and individuals and have the right to be free from any form of discrimination, in the exercise of their rights, in particular that based on their indigenous origin or identity.” Article 9 provides that “[i]ndigenous peoples and individuals have the right to belong to an indigenous community or nation, in accordance with the traditions and customs of the community or nation concerned. No discrimination of any kind may arise from the exercise of such a right.” For its part, ILO Convention 169 on Indigenous and Tribal Peoples contains the following provision in Article 3(1): “Indigenous and tribal peoples shall enjoy the full measure of human rights and fundamental freedoms without hindrance or discrimination.” These instruments enable a more precise interpretation of the scope and content of the non-discrimination clause and the right to equal protection recognized, respectively, in articles 1(1) and 24 of the American Convention, as they apply in the case of indigenous peoples. 177. As was explained above, the allegations of racial discrimination based on a “suspect” distinction, demand scrutiny on the part of international human rights bodies. In effect, as the Commission wrote, whenever some difference in treatment is based on the factors that international instruments explicitly list as prohibited discrimination, such a distinction must be subjected to particularly exacting scrutiny, in which the State is required to show a particularly important interest that the 195 distinction serves and solid grounds for such a distinction. 194 IACHR, Report on Terrorism and Human Rights, OEA/SER.L/V/II.116, Doc. 5 rev. 1, corr., October 22, 2002, paragraphs 355-356. 195 See, for example, European Court of Human Rights, case of Abdulaziz v. United Kingdom, Judgment of May 28, 1985, Ser. A No. 94, paragraph 79. IACHR, Report on Terrorism and Human Rights, OEA/SER.L/V/II.116, Doc. 5 rev. 1, corr., October 22, 2002, paragraph 338, footnote 805. IACHR, Access to Justice for Women Victims of Violence in the Americas, OEA/Ser.L/V/II.doc.68, January 20, 2007, paragraph 83. IACHR, Report No. 4/01, Case 11.625, Maria Eugenia Morales de Sierra v. Guatemala, January 19, 2001, paragraph 36. IACHR, Annual Report 1999. Considerations regarding the compatibility of affirmative action measures designed to promote the political participation of women with the principles of equality and non-discrimination, Chapter VI.