State and territory police will be given greater powers to call out the Australian Defence Force to deal with extreme violence including terrorist attacks.
Legislation cleared federal parliament on Tuesday to update military call-out parameters, with the changes coming after an inquest into the 2014 Lindt cafe siege in Sydney.
Assistant Home Affairs Minister Linda Reynolds said the powers were for cases of extreme violence likely to go beyond the remit of state and territory police.
"The incident must be of such gravity and magnitude to warrant calling out the ADF," Senator Reynolds told parliament.
Labor and crossbench senators backed the coalition's legislation, while the Greens opposed the move.
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Greens senator Nick McKim said the changes were further evidence Australia was sleepwalking toward authoritarianism.
"The Greens had absolutely nothing to do with this dog's breakfast of a piece of legislation which fails to define the terms which the army can be called out to kill Australians," he said.
Senator Reynolds confirmed acts of civil disobedience could warrant defence call-outs if there was the likelihood of damage to property, serious injury or death.
But she insisted police requests for military intervention could be rejected by the federal government, with existing safeguards still in place.
Under the changes, the ADF will be allowed to be pre-authorised to respond to threats on land, at sea and in the air.
It will also simplify and expand the military's powers to search, seize, and control movement at the scene of a terrorist incident.
Under existing arrangements, states have to declare a situation out of control and beyond their resources before the military can be called in to assist local authorities.
