Enacting and developing international environmental law - Introduction to International Environmental Law - page 54

international law. When an international organization makes plans for new
international environmental regulation, it has to consider whether a soft-
law instrument or an international convention should be selected. A soft-law
instrument allows the regulation to be implemented sooner as it does not
require ratifi cation by states; ratifi cation always delays the entry into force of
a convention. On the other hand, soft-law instruments are not legally bind-
ing and seldom engage states in any really ambitious environmental protec-
tion, whereas international conventions are binding. The judges in
international courts make their decisions on the basis of the sources of
general international law. They seek to resolve confl icts between states by
considering all the international legal regulations, not just the environmental
regulations.
Problems with the sources of international law
Although Article 38 of the Statute of the International Court of Justice provides a
solid basis for sources of international law, it leaves many questions unanswered.
Are the listed sources of equal weight, or is there some degree of hierarchy? In
principle, customary international law, conventions and general principles of law
are of equal weighting: all are considered formal sources of law and authoritative
in their own right. In practice, some are more equal than others, although there
are a few exceptions to this basic rule.
The Charter of the United Nations can be seen as the 'constitution of the
international community'; it overrides other international agreements. This is
expressed in Article 103 of the Charter which states: 'In the event of a con-
fl ict between the obligations of the Members of the United Nations under
the present Charter and their obligations under any other international agree-
ment, their obligations under the present Charter shall prevail.' This means that
provisions of the Charter (a treaty) should take precedence over other interna-
tional treaties.
Another exception from the basic rule is that the so-called jus cogens norms
override all other sources of international law. These universal principles refl ect
the basic values of the international community, and they shall be accepted by
the community of states as jus cogens norms; no derogation from them is possible
by international treaties (Vienna Convention on the Law of Treaties, Article 53).
The most important jus cogens norms are those that prohibit genocide, slavery
or torture.
There is also a debate as to whether any of the principles of international envi-
ronmental law has the status of jus cogens - being of such importance that states
cannot override it by mutual agreement. In the dispute between Hungary and
Slovakia concerning their mutual dam project, the International Court of Justice
only stated in its 1997 judgment that neither one of the parties claimed that
jus cogens norms invalidated their agreement of 1977. It is not easy to prove that
the principles of international environmental law are jus cogens norms which
cannot be overridden by an agreement.