• an obligation to provide a legal regime that effectively protects life; • laws that properly prohibit and punish killings; and • criminal sanctions against unlawful killings, regardless of who carried out the killings. This is the case even where a state agent is responsible for the taking of a life, if that use of lethal force cannot be justified and was not absolutely necessary. Deaths must be properly investigated, and the law must be effectively implemented. From a counter-terrorism perspective, the positive obligation to protect life may under certain circumstances require the state to protect individuals from identifiable threats to their lives. This positive obligation means: • having in place measures to deal with incidents of terrorism to ensure that the consequences have as little impact upon the right to life as possible; • ensuring, through appropriate planning and guidelines, that counter-terrorism measures themselves have as little impact upon the right to life as possible; • that those responsible for acts of terrorism resulting in the loss of life are pursued, prosecuted and appropriately sentenced; • that the state take all appropriate actions to ensure that such acts of terrorism do not occur in the first instance. Where it is alleged that loss of life was caused by a state agent, the European Court has held that this must be proved beyond reasonable doubt.249 However, where an individual dies in custody and the state fails to provide a satisfactory explanation, the conclusion may be that the death occurred as a result of the acts or omissions of the state authorities. Where there is a death in custody, the burden of proof falls on the state to identify the cause of death. When an individual is detained by the state, there is an obligation to ensure their health and wellbeing. This includes protecting them from committing suicide.250 The extent of the positive obligation to protect life is not limitless. An appropriate balance must be struck. If law-enforcement agencies fail to act, for example, by opting not to arrest someone who then goes on to take a life, this will not necessarily violate the right to life. In Osman,251 the Court found no violation of the right to life where the police did not arrest an individual who was harassing a family and who then went on to shoot and kill the father of that family. The police, under the circumstances, had no reason to believe such an event might occur. The Court found that the police could not be criticized for having failed to use their powers of arrest when they reasonably believed that they lacked the necessary standard of suspicion to exercise those powers. The principle that can be adduced from this case, however, is that if it can be shown that the authorities failed to take reasonable steps to avoid a real and immediate risk to life of which 249 ECtHR, Yaşa v. Turkey, Case no. 63/1997/847/1054, 2 September 1998, paras. 92-97. 250 “In the context of prisoners, the Court has already emphasised in previous cases that persons in custody are in a vulnerable position and that the authorities are under a duty to protect them. It is incumbent on the State to account for any injuries suffered in custody, which obligation is particularly stringent where that individual dies […] There are general measures and precautions which will be available to diminish the opportunities for self-harm, without infringing on personal autonomy. Whether any more stringent measures are necessary in respect of a prisoner and whether it is reasonable to apply them will depend on the circumstances of the case”, ECtHR, Keenan v. UK, Application no. 27229/95, 3 April 2001, paras. 91 and 92. 251 Op. cit., note 28, ECtHR, Osman v. UK. Countering Terrorism, Protecting Human Rights 101