environmental impact on them of planned development activities. The results of these studies shall be considered as fundamental criteria for the implementation of these activities.” 205. Conducting such studies constitutes a safeguard to guarantee that the constraints imposed on the indigenous or tribal communities with regard to their right to property when concessions are granted within their territory do not entail a denial of their survival as a people (supra para. 157). Thus, the Court has established that the State must guarantee that no concession will be granted within the territory of an indigenous community unless and until independent and technically competent bodies, under the supervision of the State, have made a prior environmental and social impact assessment.271 The Court has also determined that environmental impact assessments “serve to evaluate the possible damage or impact that a proposed development or investment project may have on the property and community in question. Their purpose is not [only] to have some objective measure of the possible impact on the land and the people, but also […] to ensure that the members of the community […] are aware of the potential risks, including the environmental and health risks,” so that they can decide whether to accept the proposed development or investment plan “knowingly and voluntarily.”272 206. In addition, the Court has established that environmental impact assessments must be made in conformity with the relevant international standards and best practices;273 respect the indigenous peoples´ traditions and culture, and be completed before the concession is granted, since one of the objectives of requiring such studies is to guarantee the right of the indigenous people to be informed about all proposed projects on their territory.274 Therefore, the State’s obligation to supervise the environmental impact assessment is consistent with its obligation to guarantee the effective participation of the indigenous people in the process of granting concessions. The Court also indicated that one of the points that should be addressed in the environmental and social impact assessment is the cumulative impact of existing and proposed projects.275 207. In this case, the Court observes that the environmental impact plan: (a) was prepared without the participation of the Sarayaku People; (b) was implemented by a private entity subcontracted by the oil company, without any evidence that it had subsequently been subject to strict control by State monitoring agencies, and (c) did not take into account the social, spiritual and cultural impact that the planned development activities might have on the Sarayaku People. Therefore, the Court concludes that the environmental impact plan was not implemented in accordance with its case law or the relevant international standards. e) The consultation must be informed 208. As indicated previously, the consultation must be informed, in the sense that the indigenous peoples must be aware of the potential risks of the proposed development or investment plan, including the environmental and health risks. Thus, prior consultation requires that the State receive and provide information, and involves constant communication between the parties. The case law of the domestic courts276 and laws277 has referred to this aspect of the consultation. 271 Cf. Mutatis mutandi, Case of the Saramaka People v. Suriname, Preliminary objections, merits, reparations and costs, para. 130. 272 Cf. Case of the Saramaka People v. Suriname. Interpretation of judgment, para. 40. 273 Cf. Case of the Saramaka People v. Suriname. Interpretation of judgment, footnote 23. 274 Cf. Case of the Saramaka People v. Suriname. Interpretation of judgment, para. 41. 275 Cf. Case of the Saramaka People v. Suriname. Interpretation of judgment, para 41. 276 The Colombian Constitutional Court has indicated that prior consultation must be addressed at ensuring that “the community has full knowledge of projects for the exploration and exploitation of natural resources on the territories that it occupies or owns, and the mechanisms, procedures and activities to execute them”; that “it is provided with information and an explanation of how the execution of the said projects may result in adverse effects or harm to the elements that constitute the foundation of the community’s social, cultural, economic and political cohesion and, consequently, the basis for its survival as a human group with unique characteristics,” and that “it has the opportunity, freely and without outside interference, to assess with full awareness, by consulting with its members or representatives, the advantages and 59