instance, Resolution 2240 (2015) on migrant smuggling off the coast of Libya does
not contain any reference to customary international law.
In the framework of sanctions and embargoes, the Security Council rarely
mentions the hypothetical formation of a customary rule, but it can nevertheless
happen, for instance in Resolution 2146 (2014), the Council:
[f]urther affirms that the authorization provided by paragraph 5 of this resolution applies
only with respect to vessels that are the subject of a designation made by the Committee
pursuant to paragraph 11 and shall not affect the rights or obligations or responsibilities
of Member States under international law, including rights or obligations under the
United Nations Convention on the Law of the Sea, including the general principle of
exclusive jurisdiction of a flag state over its vessels on the high seas, with respect to other
vessels and in any other situation, and underscores in particular that this resolution shall not
be considered as establishing customary international law.
32
3.2 Legal Effects of the Exclusion Clauses
These clauses aim at preventing a customary norm from arising from practice and
States from applying the authorisations granted by UNSC to other situations when
confronted with similar issues (i.e. the Gulf of Guinea for piracy, other parts of the
Mediterranean Sea for migrant smuggling, etc.). If we accurately understand why the
Council would insert these garde-fou, it nevertheless gives rise to a series of
questions on the formation of customary international law and the powers of the
UNSC. In other words, can the Security Council prevent the formation of a customary rule, especially if this rule would be based on practice arising from the implementation of its own resolutions?
The draft conclusions of the International Law Commission on the identification
of customary international law indicates that “[a] resolution adopted by an international organization or at an intergovernmental conference cannot, of itself, create a
rule of customary international law.”
33 It can only “provide evidence for establishing
the existence and content of a rule of customary international law, or contribute to its
development.”
34 Hence, if a unilateral act of an international organisation cannot, of
itself, create a customary rule, it cannot, of itself, prohibit its creation either. It must
be established, on a case-by-case basis, if the two elements of customary international law are met, namely a consistent practice and opinio juris. That being said, the
Council does not seem to want to prevent the formation of customary rules in
general, but only to make sure that the authorisations given by it do not affect the
rights and obligations under the International Law of the Sea. In other words, the
Council intends to prevent the creation of such a rule if the practice is based on its
32 Para. 9.
33 Conclusion 12 (1), 30 May 2016, A/CN.4/L.872, Text of the draft conclusions provisionally
adopted by the Drafting Committee.
34 Id., Conclusion 12 (2).
186
K. Neri
not contain any reference to customary international law.
In the framework of sanctions and embargoes, the Security Council rarely
mentions the hypothetical formation of a customary rule, but it can nevertheless
happen, for instance in Resolution 2146 (2014), the Council:
[f]urther affirms that the authorization provided by paragraph 5 of this resolution applies
only with respect to vessels that are the subject of a designation made by the Committee
pursuant to paragraph 11 and shall not affect the rights or obligations or responsibilities
of Member States under international law, including rights or obligations under the
United Nations Convention on the Law of the Sea, including the general principle of
exclusive jurisdiction of a flag state over its vessels on the high seas, with respect to other
vessels and in any other situation, and underscores in particular that this resolution shall not
be considered as establishing customary international law.
32
3.2 Legal Effects of the Exclusion Clauses
These clauses aim at preventing a customary norm from arising from practice and
States from applying the authorisations granted by UNSC to other situations when
confronted with similar issues (i.e. the Gulf of Guinea for piracy, other parts of the
Mediterranean Sea for migrant smuggling, etc.). If we accurately understand why the
Council would insert these garde-fou, it nevertheless gives rise to a series of
questions on the formation of customary international law and the powers of the
UNSC. In other words, can the Security Council prevent the formation of a customary rule, especially if this rule would be based on practice arising from the implementation of its own resolutions?
The draft conclusions of the International Law Commission on the identification
of customary international law indicates that “[a] resolution adopted by an international organization or at an intergovernmental conference cannot, of itself, create a
rule of customary international law.”
33 It can only “provide evidence for establishing
the existence and content of a rule of customary international law, or contribute to its
development.”
34 Hence, if a unilateral act of an international organisation cannot, of
itself, create a customary rule, it cannot, of itself, prohibit its creation either. It must
be established, on a case-by-case basis, if the two elements of customary international law are met, namely a consistent practice and opinio juris. That being said, the
Council does not seem to want to prevent the formation of customary rules in
general, but only to make sure that the authorisations given by it do not affect the
rights and obligations under the International Law of the Sea. In other words, the
Council intends to prevent the creation of such a rule if the practice is based on its
32 Para. 9.
33 Conclusion 12 (1), 30 May 2016, A/CN.4/L.872, Text of the draft conclusions provisionally
adopted by the Drafting Committee.
34 Id., Conclusion 12 (2).
186
K. Neri