Quarantine in times of emergency: the scope of s 51(ix) of the Constitution

This article explores the scope of s 51(ix) of the Constitution, the power of the Commonwealth to make laws with respect to "quarantine". While this power has sustained the Quarantine Act without a challenge since 1908, it may be that future national public health emergencies, such as epidemics or bioterrorism, will (as has happened in other countries) demand a level of federal preparedness that requires augmented public health powers at a national level. If so, will the scope of the quarantine power, as determined by the High Court, be wide enough allow the Commonwealth to implement these powers? While there is some advantage in a national approach, there is also some authority suggesting that the quarantine power could not extend to domestic public health controls. If there is uncertainty about the scope of the power, what are the options? Should there be another approach, with the States, Territories and the Commonwealth moving towards uniform legislation and co-operative arrangements?