Why is June 3 observed as Mabo Day in Australia?

Mabo Day is observed annually on June 3 to commemorate the landmark 1992 decision by the High Court of Australia in the case of Mabo v. Queensland (No. 2).1

This historic ruling was the culmination of a decade-long legal battle led by Meriam activist Eddie Koiki Mabo. The court’s decision fundamentally changed Australian law by overturning the doctrine of terra nullius—the colonial legal fiction that Australia was "land belonging to no one" prior to European settlement.12

By declaring terra nullius null and void, the High Court formally recognized the pre-existing land rights of Torres Strait Islander peoples and Aboriginal peoples, thereby establishing the concept of "native title" in Australia. This recognition was a monumental victory for Indigenous communities, as it acknowledged their traditional ownership of the land and provided a legal pathway for them to pursue land claims and compensation.12