138. The Court reiterates that, as regards the question whether the State could be held responsible, under Article 3, for ill-treatment inflicted on persons by non-State entities, the obligation on the High Contracting Parties under Article 1 of the Convention to secure to everyone within their jurisdiction the rights and freedoms defined in the Convention, taken together with Article 3, requires States to take measures designed to ensure that individuals within their jurisdiction are not subjected to torture or inhuman or degrading treatment or punishment, including such ill-treatment administered by private individuals (see, mutatis mutandis, HLR v France, 29 April 1997, para 40, Reports 1997-III). These measures should provide effective protection, in particular, of children and other vulnerable persons, and include reasonable steps to prevent ill-treatment of which the authorities had or ought to have had knowledge (see, mutatis mutandis, Osman v United Kingdom, 28 October 1998, para 116, Reports 1998-VIII, and E and Others v United Kingdom, Application no 33218/96, para 88, 26 November 2002).
139. Bearing in mind the difficulties in policing modern societies, the unpredictability of human conduct and the operational choices which must be made in terms of priorities and resources, the scope of this positive obligation must, however, be interpreted in a way which does not impose an impossible or disproportionate burden on the authorities. Not every claimed risk of ill-treatment, thus, can entail for the authorities a Convention requirement to take operational measures to prevent that risk from materialising. For a positive obligation to arise, it must be established that the authorities knew or ought to have known at the time of the existence of a real and immediate risk of ill-treatment of an identified individual from the criminal acts of a third party and that they failed to take measures within the scope of their powers which, judged reasonably, might have been expected to avoid that risk. Another relevant consideration is the need to ensure that the police exercise their powers to control and prevent crime in a manner which fully respects the due process and other guarantees which legitimately place restraints on the scope of their action to investigate crime and bring offenders to justice, including the guarantees contained in Article 8 of the Convention (see Mubilanzila Mayeka and Kaniki Mitunga v Belgium, Application no 13178/03, para 53, ECHR 2006-XI; Members (97) of the Gldani Congregation of Jehovah’s Witnesses v Georgia, Application no 71156/01, para 96, 3 May 2007; and Milanovi´c v Serbia, Application no 44614/07, para 84, 14 December 2010; see also, mutatis mutandis, Osman, cited above, para 116).
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(i) General principles
151. While the essential object of Article 8 is to protect the individual against arbitrary interference by public authorities, it does not merely compel the State to abstain from such interference: in addition to this negative undertaking, there may be positive obligations inherent in effective respect for private or family life. These obligations may involve the adoption of measures designed to secure respect for private life even in the sphere of the relations of individuals between themselves (see X and Y v The Netherlands, cited above, para 23; Botta v Italy, 24 February 1998, para 33, Reports 1998-I; Mikuli´c v Croatia, Application no 53176/99, para 57, ECHR 2002-I; and Sandra Jankovi´c, cited above, para 44).
152. The court has previously held, in various contexts, that the concept of private life includes a person’s psychological integrity. Under Article 8, States have in some circumstances a duty to protect the moral integrity of an individual from acts of other persons. The court has also held that a positive obligation exists upon States to ensure respect for human dignity and the quality of life in certain respects (see L v Lithuania, Application no 27527/03, para 56, ECHR 2007-IV, and, mutatis mutandis, Pretty v United Kingdom, Application no 2346/02, para 65, ECHR 2002-III).
(ii) Application of these principles to the present case
153. The court considers that the acts of ongoing harassment have also affected the private and family life of the second applicant. It has found that the State authorities have not put in place adequate and relevant measures to prevent further harassment of the first applicant. Likewise, the State authorities have failed to afford adequate protection in that respect to the second applicant. Therefore, there has also been a violation of Article 8 of the Convention in respect of the second applicant.