It implies that the imposition of criminal liability is limited to clear and precise provisions, so as to respect the principle of certainty of the law and ensure that it is not subject to interpretation which would unduly broaden the scope of the proscribed conduct. Overly vague or broad definitions of terrorism may be used by States as a means to cover peaceful acts to protect inter alia labour rights, minority rights or human rights or, more generally, to limit any sort of political opposition.86 As mentioned earlier, none of the current international conventions on anti-terrorism contains a comprehensive definition of the term terrorism. Neither do resolutions of the various United Nations bodies set out a comprehensive definition. Instead, the conventions are “sectoral” in nature and address specific subjects, whether air safety, maritime navigation and platforms, the protection of persons, or the suppression of the means by which terrorist acts may be perpetrated or supported. As mentioned in chapter I, section B, negotiations on a draft comprehensive convention on international terrorism, referred in 2001 to a committee of the General Assembly, continue. Importantly, the draft convention contains a comprehensive definition in its article 2. In view of its comprehensive approach, the adoption of the draft convention would contribute to strengthening the international legal framework by consolidating a number of criminal conducts that the existing, “sectoral” universal conventions do not cover. However, certain aspects of the draft convention remain controversial, in particular the scope of application of the proposed definition of terrorist offences and whether national liberation movements should be excluded or not from its scope of application, as well as its interplay with other provisions of international law.87 Moreover, even if a comprehensive definition is agreed upon at international level, human rights concerns may still arise depending on the definition of terroristrelated offences adopted nationally. In 2004, the Security Council adopted resolution 1566 (2004), in which it called on all States to cooperate fully in the fight against terrorism and, in doing so, to prevent and punish criminal acts that have the following three characteristics, irrespective of whether motivated by considerations of a political, philosophical, ideological, racial, ethnic, religious or other similar nature: • Committed, including against civilians, with the intent to cause death or serious bodily injury, or taking of hostages; and • Committed with the purpose to provoke a state of terror in the general public or in a group of persons or particular persons, 40