The attack violated Governor Macquarie's instructions to seek the Aboriginals' surrender as "prisoners of war" and to preserve the lives of women and children.
He appointed military units around settlements to clear the land of natives and to set examples, through force and the taking of hostages, of those who resisted colonial power.
[4] Governor Macquarie efficaciously declared war on "hostile natives" in New South Wales, appointing a campaign of "terror" against those who violently resisted British rule, ordering those who did not surrender to be killed and their corpses hung up on trees as warnings, and those that did to be taken hostage as prisoners of war, until the guilty ones surrender themselves or be exposed by their tribes for justice.
Governor Lachlan Macquarie ordered an armed reprisal "to inflict exemplary and severe punishment on the mountain tribes...to strike them with terror...clearing the country of them entirely."
In the early morning of 17 April, at around 1 am, Wallis led a surprise attack on this camp with "smart firing" resulting in the deaths of at least fourteen Aboriginal people from both gunshot wounds or from falling off the rocky cliffs around the river while fleeing.
Wallis took two surviving women and three children prisoner and, following the orders of Governor Macquarie, hung the corpses of Cannabaygal and Dunnell from trees on a hill near Appin to "strike the survivors with greater terror.
An official proclamation launched regulations to control Aboriginal people, including limiting their movements and prescribing what they may carry on their person.
The law also prohibited large Aboriginal assemblages and discussed supplying passports, an authentication mark of future protectionist policies.