A selection of key paragraph(s) can be found below the document.CASE-OF-KONTROVA-v.-SLOVAKIA
50. 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 the positive obligation must be interpreted in a way which does not impose an impossible or disproportionate burden on the authorities. Not every claimed risk to life, therefore, 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 to the life 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 (ibid., pp. 3159-60, § 116).