Commonwealth Police

The name Commonwealth Police referred, officially or informally, to federal law enforcement organisations in Australia between 1917 and 1979. In late 1979, the Commonwealth Police and Australian Capital Territory Police were merged to form the Australian Federal Police (AFP).

Initially, after the six British colonies in Australia federated in 1901, there was no police agency to enforce federal (Commonwealth) laws. Instead, the various State police forces were called upon by the Commonwealth as required.

During the latter stages of World War I, there was considerable tension within Australian society, particularly over the issue of introducing military conscription. On 29 November 1917, at a public rally over this issue in the rural Queensland township of Warwick, an egg was thrown at Australian Prime Minister Billy Hughes. The offender was charged under Queensland state law, whereas Hughes wanted a Commonwealth charge preferred. The incident, and the perceived lack of action on the part of the Queensland Police, was the last straw for Hughes, who had spent months arguing and fighting with the government of Queensland, led by its anti-conscriptionist Premier T. J. Ryan, over a range of issues. Hughes doubted the loyalty of several prominent Queensland politicians and public servants, and felt that it was necessary to create a Commonwealth Police Force to ensure that Commonwealth law was adhered to in what he regarded as a "rogue" state.

Under the War Precautions Act, 1914, Hughes quickly created a plain-clothed police force, which commenced operations in mid-December 1917. Hughes claimed Australia was at risk from possible revolt or similar action by organisations associated with either Irish nationalism, left wing and anti-war activities, such as Sinn Féin and the Industrial Workers of the World. At its peak the Commonwealth Police Force numbered about 50 men, almost all of whom were based in Queensland, despite the force notionally being a national one. Commonwealth Police had full police powers for federal offences, but their main task was to report on subversive activities of those opposed to the war and/or the Commonwealth government. Tensions between the Queensland and federal governments flared up a number of times, including during and after a federal police raid on the Queensland Government Printer's Office.

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