What is the hierarchy of norms in the UN legal order?

A "hierachy of norms" refers to the order of importance in which a norm is considered within a legal system. For matters internal to the organization, the hierarchy of norms in the UN has been set out in certain judgments of the UN Dispute Tribunal as follows:

• Charter of the United Nations
• Resolutions and decisions
• Staff regulations
• Staff rules
• Secretary-General's bulletins
• Administrative instructions

From Villamoran v. Secretary-General of the United Nations (Judgment No. UNDT/2011/126), paragraph 29:

At the top of the hierarchy of the Organization’s internal legislation is the Charter of the United Nations, followed by resolutions of the General Assembly, staff regulations, staff rules, Secretary-General’s bulletins, and administrative instructions (see Hastings UNDT/2009/030, affirmed in Hastings 2011-UNAT-109; Amar UNDT/2011/040). Information circulars, office guidelines, manuals, and memoranda are at the very bottom of this hierarchy and lack the legal authority vested in properly promulgated administrative issuances. 

Legal opinions of the Secretariat and Advisory Opinions of the International Court of Justice may also provide information on the interpretation of legal matters within the UN. 

• The UN Juridical Yearbook includes, among other useful information:
  • A general review of the legal activities of the UN
  • Selected decisions of the administrative tribunals of the UN
  • Selected legal opinions of the secretariats of the UN
  • Selected judicial decisions on questions relating to the UN from both international and national tribunals

More broadly, Schermers and Blokker, in International Institutional Law, 5th rev. ed, 2011, section 1145, state: 

The constitution sets the pattern for the legal order of the international organization. Further rules develop from the operation of its organs. The power of these organs to take decisions stems from the constitution. From this common source, a hierarchy of the various legal rules is developed, and a single legal order thus created. The validity of each rule will depend on the constitution, the basis of the legal order. 

In the larger context of the international community and its legal order, the role of the Charter in public international law in general is a topic of scholarly debate. Many books, articles, courses and lectures concern the position of the UN Charter within the hierarchy (or hierarchies) of norms in public international law.

Some key terms are: hierarchy of norms, conflict of norms, fragmentation of international law, unity of international law, interpretation, jus cogens, obligations, international system, international legal order, sources of international law

Some key provisions are: 

• Article 38 of the Statute of the International Court of Justice, concerns sources of international law
• Article 103 of the Charter, concerns conflict between the Charter and other treaty obligations
• Article 30 of the Vienna Convention on the Law of Treaties, concerns Article 103 of the Charter and other treaties
• Articles 31-33 of the Vienna Convention on the Law of Treaties, concern interpretation of treaties

National and international courts and tribunals may be called upon to interpret treaty provisions

• For example, see discussions of the Kadi cases in the European Union courts, which concerned, in part, the relationship between obligations of UN Member States under Chapter VII of the Charter and their obligations under other elements of the international legal order, such as EU regulations.