measures being taken to prevent it or to punish those responsible.” 191 In order to comply with this obligation, it is not sufficient that States merely abstain from violating rights; rather it is essential that States take all appropriate measures to protect and preserve the rights of all those under their jurisdiction (positive obligation), in keeping with their obligation to ensure the free and full exercise of those rights.192 187. In addition, the Court has held that, in certain circumstances, the prompt and resolute investigation of alleged threats may contribute, in turn, to prevent the violation of the rights that were being threatened.193 188. The Court has noted that this obligation to investigate remains in effect “whatsoever the agent to whom the violation may eventually be attributed, even private individuals, because, if their acts are not investigated seriously, they would, to a certain extent, be supported by the public authorities, which would involve the international responsibility of the State.”194 Regarding the State’s obligation to adopt measures of prevention and protection, the Court has recognized that this does not imply its unlimited responsibility for any act or deed of private individuals, because its obligation to adopt measures of prevention and protection for private individuals in their relations with each other is conditional on its awareness of a situation of real and imminent danger for a specific individual or group of individuals and the reasonable possibility of preventing or avoiding that danger.195 189. In addition, the Court has stated that the effective exercise of freedom of expression entails the existence of social conditions and practices that favor it. It is possible that this freedom may be illegally restricted by regulatory or administrative acts of the State or due to de facto conditions that place those who exercise or try to exercise it in a direct or indirect situation of risk or greater vulnerability due to acts or omissions of State agents or private individuals. Within the framework of its obligations to guarantee the rights acknowledged in the Convention, the State must abstain from acting in a way that encourages, promotes, favors, or intensifies that vulnerability,196 and it must adopt, when pertinent, the necessary and reasonable measures to prevent or protect the rights of those who are in that situation, as well as, when appropriate, to investigate acts that harm them.197 190. Consequently, failure to comply with the obligation to guarantee the rights protected in Articles 5 and 13 of the Convention by adopting measures of protection and conducting a 191 Cf. Case of Velásquez Rodríguez v. Honduras. Merits, para. 173, and Case of the Barrios Family v. Venezuela. Merits, reparations and costs, para. 47. 192 Cf. Case of Velásquez Rodríguez v. Honduras. Merits, paras. 166 and 167, and Case of the Barrios Family v. Venezuela. Merits, reparations and costs, para. 116. 193 Cf. Case of Velásquez Rodríguez v. Honduras. Merits, paras. 174 and 175, and Case of Manuel Cepeda Vargas v. Colombia. Preliminary objections, merits, reparations and costs, para. 101. 194 Cf. Case of Velásquez Rodríguez v. Honduras. Merits, para. 177, and Case of González Medina and family members v. Dominican Republic. Preliminary objections, merits, reparations and costs, para. 206. 195 Cf. Case of the Pueblo Bello Massacre v. Colombia. Merits, reparations and costs. Judgment of January 31, 2006. Series C No. 140, para. 123, and Case of the Barrios Family v. Venezuela. Merits, reparations and costs, para. 123. 196 Cf. Juridical Status and Rights of Undocumented Migrants. Advisory Opinion OC-18/03 of September 17, 2003. Series A No. 18, paras. 112 to 172, and Case of Vélez Loor v. Panamá. Preliminary objections, merits, reparations and costs. Judgment of November 23, 2010. Series C No. 218, para. 207. 197 Cf. Case of Ríos et al. v. Venezuela. Preliminary objections, merits, reparations and costs, para. 107, and Case of Vélez Loor v. Panamá. Preliminary objections, merits, reparations and costs, para. 207. 57