14. Before looking at the various sources, systems and standards existing at the international level, a word about the legal force of these standards is in order. The collective body of standards discussed in this Manual spans the full range of international legal authority, from binding obligations set out in covenants and conventions to morally persuasive universal guidance offered through various declarations, minimum rules, and bodies of principles. Together, these instruments offer a comprehensive and detailed international legal framework for ensuring respect for human rights, freedom and dignity in the context of criminal justice. 15. In strict legal terms, formal treaties which have been ratified or acceded to by States, as well as customary international law, have the character of binding law. Such treaties include the following: ■ International Covenant on Economic, Social and Cultural Rights; ■ International Covenant on Civil and Political Rights; ■ Convention on the Rights of the Child; ■ Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment; ■ International Convention on the Elimination of All Forms of Racial Discrimination; ■ Convention on the Elimination of All Forms of Discrimination against Women; ■ Convention on the Prevention and Punishment of the Crime of Genocide. Mention should also be made of the Charter of the United Nations, itself a legally binding treaty to which all Member States are parties. 16. In addition, customary international law is the term used to describe general and consistent practice followed by States deriving from a sense of legal obligation. In other words, if over a period of time States perform in a certain way because they believe that they are required to do so, that behaviour comes to be recognized as a principle of international law, binding on States, even if not written in a particular agreement. 17. Human rights standards are also enshrined in other types of instruments: declarations, recommendations, bodies of principles, codes of conduct and guidelines (such as the Basic Principles on the Use of Force and Firearms by Law Enforcement Officials; the Code of Conduct for Law Enforcement Officials; and the Guidelines on the Role of Prosecutors). These instruments are not legally binding on States in and of themselves. Nevertheless, the various declarations, guidelines and minimum rules, which are discussed in this Manual hand in hand with the relevant conventions, have moral force and provide practical guidance to States in their conduct. The value of these instruments rests on their recognition and acceptance by a large number of States and, even without binding legal effect, they may be seen as declaratory of principles that are broadly accepted within the international community. What is more, some of their provisions, particularly relevant to the purpose of this Manual, are declaratory of elements of customary international law and are thus binding. 7