Can the high court of australia declare a law to be invalid?

Yes. The High Court of Australia has the power to declare a law to be invalid if it finds that the law is inconsistent with the Constitution of Australia. This power is known as the 'doctrine of judicial review'.

The High Court has exercised this power on a number of occasions to strike down laws that it has found to be unconstitutional. For example, in 1992 the High Court declared that the Commonwealth's Native Title Act 1993 was invalid because it was inconsistent with the Racial Discrimination Act 1975.

The High Court's power of judicial review is an important check on the power of the Parliament to make laws. It ensures that the Parliament cannot make laws that are inconsistent with the Constitution. This power is essential to the maintenance of the rule of law in Australia.