Field had resigned from the Education Department immediately before his Senate appointment, but there was a dispute about whether he remained a public servant when appointed because the Education Act required him to give three weeks' notice. That may have made him constitutionally ineligible to be chosen as a senator, so the Labor Party challenged his appointment in the High Court. Thus, he was on leave from the Senate after 1 October 1975, unable to exercise a vote. He had not given his maiden speech and had asked only a single question in Question Time.