Victorian Liberal Senator Judith Troeth spoke frankly this morning about the high political and personal cost of opposing her own party on the Migration Bill last August.

Troeth said she and other Liberal opponents of the legislation had been subjected to “private pressure” from colleagues but also an “intense public relations campaign …”.

Words were used such as “heretic, anarchist and traitor”.

“The suggestion was that we deserved less respect”. A number of her colleagues were threatened over their preselection, she said.

Troeth said “meaningful dissent” was a matter of politics and principle, but also a matter of political survival.

“I looked at the Bill and I thought I cannot agree with this,” she said.

Troeth said that she then had to think about how to balance her loyalty to the Prime Minister and the Liberal Party with her principled opposition to the legislation, which would have seen all asylum seekers who arrived by boat processed offshore in Nauru.

“I am a loyal Liberal. I did not want to denigrate the Prime Minister who I respect and admire very much,” she said.

The Government decided not to proceed with the legislation as a result of the opposition of various senators, including Troeth, Barnaby Joyce and Family First’s Steve Fielding.

Troeth said this morning that once the decision had been made to withdraw the legislation the public denunciation of the “rebels” stopped, but there had nevertheless been a political cost.

“There is no doubt that meaningful dissent can damage with your colleagues and it is not easy,” she said.

Troeth was speaking to the Royal Melbourne Institute of Technology’s annual Public Relations breakfast this morning. Her topic was politics and principle.

Troeth said that she had been bolstered by public support, but had made a decision not to do media interviews after the legislation was withdrawn.