Early candidacies

Colston joined the Australian Labor Party in 1958 at the age of 19, following his parents into the party. He unsuccessfully sought ALP preselection for the seat of Cooroora prior to the 1963 Queensland state election. He first stood for federal parliament at the 1970 Senate election, placed third on the ALP ticket.^[1]

Colston unsuccessfully sought Senate preselection prior to the 1972 federal election, but following a double dissolution in 1974 he was placed fifth on the party's Senate ticket in Queensland. He was narrowly defeated by Country Party candidate Glen Sheil for the final vacancy. The expectation of Colston's victory was such that he was invited to attend the first meeting of the ALP caucus after the election and was able to vote on the composition of the third Whitlam ministry.^[1] In 1975 he published a book, The Odd One Out, about his experiences.^[3]

Role in 1975 constitutional crisis

Colston indirectly played a role in the 1975 Australian constitutional crisis.

On 30 June 1975, Queensland ALP Senator Bert Milliner died suddenly. The Labor Party nominated Colston to fill the casual vacancy in the Senate. The Constitution provides that a Senate casual vacancy is filled by a person chosen by the relevant state parliament. Although not a constitutional requirement until 1977, it was long a convention for the state parliament to choose a person nominated by the departing Senator's political party. However, the Premier of Queensland, Joh Bjelke-Petersen, claimed that Colston was a "dangerous socialist" and refused to appoint him. Officially, though, Bjelke-Petersen expressed doubts over Colston's integrity and instead appointed Albert Field, a member of the Labor Party who was staunchly opposed to the policies of the Gough Whitlam Labor government.^[4]

The ALP challenged Field's appointment in the High Court, and Field was on leave from the Senate almost from the day of his appointment. That gave the Coalition a greater advantage and so was one of the crucial events that led to the dismissal of the Whitlam government.

Labor Senator

At the ensuing 1975 election, Colston was elected as a Labor senator. He continued to serve in that capacity until 1996.

From 1993 to his retirement, he was a joint Father of the Senate, along with Brian Harradine.

Resignation from Labor Party

After the 1996 election, the Labor Party refused to nominate Colston to become Deputy President of the Senate, a position he had previously held from 1990 to 1993. In a bid to win him over, the Howard Coalition government offered to support him. Colston resigned from the Labor Party by fax message at 11:30 a.m., on 20 August, and he took his seat as an independent that afternoon. In the evening, he was elected Deputy President, on the nomination of the Coalition. He opposed the Coalition's industrial relations package, but he voted for the sale of a third of Telstra and some other government initiatives. Colston then sat as a "Queensland First" senator. Labor Senator Robert Ray later dubbed Colston the "Quisling Quasimodo from Queensland".^[5]

Travel allowances scandal

In 1997, Colston was charged by the Commonwealth Director of Public Prosecutions with 28 charges of defrauding the Commonwealth by allegedly misusing his parliamentary travel allowance. He then revealed that he was suffering from cancer. Prosecution was not pursued after medical opinion was provided that Colston was unlikely to live long enough for a trial to be completed. In the event, he survived for a further six years. He retired from the Senate at the end of his term.