In 1975 he was chosen as a Senator in unusual circumstances that played a significant role in precipitating the 1975 Australian constitutional crisis.
Following the usual practice, the Labor Party nominated only one person, Mal Colston, to replace Milliner.
That was precisely the sort of person wanted by Bjelke-Petersen, who responded by nominating Field in the Parliament of Queensland as the new senator.
Malcolm Fraser, the federal opposition leader, had misgivings and stated publicly that Colston's name should have been accepted.
[1] Field was expelled from the Labor Party for offering his name for Senate selection against the official ALP candidate.
That may have made him constitutionally ineligible to be chosen as a senator, so the Labor Party challenged his appointment in the High Court.
This gave the opposition a majority in the Senate, allowing it to pass motions to defer consideration of supply, and thereby force the 1975 Australian constitutional crisis.
[1] The controversy surrounding his and Cleaver Bunton's appointments prompted an amendment to the Constitution in 1977 to require casual Senate vacancies to be filled by a member of the same party.