PART 1 would impact on the nature of the international legal framework around trafficking.9 Custom is also an important constitutive element of the so-called “secondary rules” of international law – those rules that concern the circumstances under which a State is to be held responsible for a particular violation of international law, and the consequences of a finding of responsibility. It is therefore of particular relevance to the discussion of State responsibility as it relates to trafficking (see part 2.1, sections 2.1-2.4, below). 2.4. GENERAL PRINCIPLES OF LAW General principles of law are rules or principles that are found across the major legal systems of the world. Once recognized as such, general principles operate to bind States, even if they are not part of a treaty or customary law. General principles are often of a procedural and administrative kind that relate to international law as a system of law. Examples include the principle of “res judicata” (once a matter has been definitely decided by a court, it cannot be decided again); good faith; judicial impartiality; and proportionality. General principles of law can also exist at the regional, rather than universal, level. For example, the right to remain silent when charged with a crime may well be a general principle of law in Europe and the Americas, as most countries in both regions recognize it in their legal system. However, it is unclear whether it would constitute a general principle of law internationally because many countries in other parts of the world do not specifically recognize it. Conversely, the principle that someone should not be held responsible for a crime they were compelled to commit is widely accepted. General Principles of Law are occasionally relevant to the issue of trafficking and are therefore referred to at several points in this Commentary. See further Anne Gallagher, International Law of Human Trafficking (forthcoming), chap. 3. 9 24 2.5. SUBSIDIARY SOURCE: THE DECISIONS OF INTERNATIONAL COURTS AND TRIBUNALS The decisions of international courts and tribunals are an increasingly important source of law (or source of evidence of law) as a greater number of such bodies are established to deal with a range of issues – from international criminal law (the International Criminal Court and the ad hoc and hybrid tribunals that preceded or have followed it) to the Law of the Sea (the International Tribunal for the Law of the Sea); to matters related to international trade (the World Trade Organization and its Appellate Body); to regional and human rights courts (the European Court of Human Rights). The international law generating capacity of a particular court or tribunal will depend on a range of factors including the rules under which it operates, its jurisdiction and composition. In most cases, such bodies will have a less direct role: their proceedings and judgements might provide insight into or confirmation of the state of a particular customary rule, the existence of a general principle of law, or the substantive content of a particular treaty-based norm. National courts will often make use of international law and their decisions can be helpful in the task of identifying the substantive content of particular rules. Such bodies can also be useful in identifying State practice. However, their determinations do not, of themselves, constitute a source of international law or binding international legal authority. 2.6. RELEVANT “SOFT LAW” Not all international instruments relevant to trafficking are legally enforceable treaties. Declarations, guidelines, codes, memoranda of understanding, “agreements”, United Nations resolutions, interpretive texts, the pronouncements RECOMMENDED PRINCIPLES AND GUIDELINES ON HUMAN RIGHTS AND HUMAN TRAFFICKING