Opinio juris is an important concept in international law.

To be considered opinio juris, a rule must satisfy two criteria.

Which two of the following answers constitute the test for opinio juris?

Select one or more:

a.

States obey this rule because they consider themselves legally bound it (i.e. not just because of tradition, politeness, or convenience)

b.

The rule must be recognised by states with reference to the principle of distinction

c.

The rule must be recognised by states as proportionate, necessary, and adequate for purpose

d.

It is settled and uncontroversial practice of states to act (with general consistency) in obedience to the rule