Canada's judiciary plays an important role in interpreting laws and has the power to strike down Acts of Parliament that violate the constitution. The Supreme Court of Canada is the highest court and final arbiter and has been led since December 18, 2017, by Richard Wagner, the chief justice of Canada. Its nine members are appointed by the governor general on the advice of the prime minister and minister of justice. All judges at the superior and appellate levels are appointed after consultation with non-governmental legal bodies. The federal Cabinet also appoints justices to superior courts in the provincial and territorial jurisdictions.