tax and federation

At Federation in 1901, the Australian Constitution granted the Commonwealth a monopoly of customs duties and excises and the power to levy other taxes concurrently with the States. One of the significant results of Federation was the removal of all duties on goods traded between Australian states. 

By Federation, many of the colonies had introduced income taxes, each with their own definition of assessable income and different rates applying to differing categories of income. Income taxation was further complicated by some jurisdictions taxing according to the taxpayer’s residency and others taxing according to where income was earned.