The battle over rights in Switzerland: populist arguments against international law

If there is a genuine conflict of laws between federal and inter national
law, Switzerland’s obligation under international law takes precedence;
this applies even to agreements that do not concern human
rights or fundamental freedoms. The precedence set out above also
applies in relation to subsequent federal laws, i.e. those which have
entered into force in accordance with international law; the lex posterior
rule does not apply in the relationship between international
law and national law. Switzerland cannot invoke its domestic law to
justify the non-fulfilment of a treaty. Accordingly, federal legislation
contrary to international law remains regularly inapplicable. (Federal
Court Ruling BGE (2012) 139 I 16, p. 28)