GIULIANI AND GAGGIO v. ITALY JUDGMENT 65 incompatible with effective respect for human rights. This means that policing operations must be sufficiently regulated by national law, within the framework of a system of adequate and effective safeguards against arbitrariness and abuse of force. Accordingly, the Court must take into consideration not only the actions of the agents of the State who actually administered the force but also all the surrounding circumstances, including such matters as the planning and control of the actions under examination. Police officers should not be left in a vacuum when performing their duties: a legal and administrative framework should define the limited circumstances in which law-enforcement officials may use force and firearms, in the light of the international standards which have been developed in this respect (see Makaratzis, cited above, §§ 58-59). 250. In particular, law-enforcement agents must be trained to assess whether or not there is an absolute necessity to use firearms, not only on the basis of the letter of the relevant regulations, but also with due regard to the pre-eminence of respect for human life as a fundamental value (see Nachova and Others, cited above, § 97; see also the Court's criticism of the “shoot to kill” instructions given to soldiers in McCann and Others, cited above, §§ 211-214). 251. Lastly, it should not be overlooked that Carlo Giuliani's death occurred in the course of a mass demonstration. While it is the duty of Contracting States to take reasonable and appropriate measures with regard to lawful demonstrations to ensure their peaceful conduct and the safety of all citizens, they cannot guarantee this absolutely and they have a wide discretion in the choice of the means to be used. In this area the obligation they enter into under Article 11 of the Convention is an obligation as to measures to be taken and not as to results to be achieved (see Plattform “Ärzte für das Leben” v. Austria, 21 June 1988, § 34, Series A no. 139; Oya Ataman v. Turkey, no. 74552/01, § 35, ECHR 2006-XIII; and Protopapa v. Turkey, no. 16084/90, § 108, 24 February 2009). However, it is important that preventive security measures such as, for example, the presence of first-aid services at the site of demonstrations, be taken in order to guarantee the smooth conduct of any event, meeting or other gathering, be it political, cultural or of another nature (see Oya Ataman, cited above, § 39). Moreover, where demonstrators do not engage in acts of violence, it is important for the public authorities to show a certain degree of tolerance towards peaceful gatherings if the freedom of assembly guaranteed by Article 11 of the Convention is not to be deprived of all substance (see Patyi and Others v. Hungary, no. 5529/05, § 43, 7 October 2008). On the other hand, interferences with the right guaranteed by that provision are in principle justified for the prevention of disorder or crime and for the protection of the rights and freedoms of others where demonstrators engage in acts of violence (see Protopapa, cited above, § 109).