Several senior South Australian Liberals have privately apologised to Labor front-bencher Chloe Fox over a parliamentary slur from deputy opposition leader Mitch Williams.

In Legislative Assembly question time yesterday, Williams, whose party room support is rapidly evaporating, asked Fox whether she had excluded herself from a Cabinet vote over suppression orders for accused s-x offenders because of her “conflict of interest”.

Chloe Fox’s father Malcolm was convicted in July of an affair with a former pupil in the 1980s and later handed a suspended sentence.

Yesterday’s question, which received verbal endorsement from opposition leader Isobel Redmond, sparked outrage on the government benches and drew a swift rebuke from speaker Lyn Breuer.

And Crikey can reveal that senior Liberal colleagues were also horrified that Williams had gone there. Chloe Fox confirmed to Crikey this morning she was approached after question time by senior opposition MPs keen to distance themselves from the attack.

“I was approached privately and they were genuine apologies,” she said.

Crikey understands the rogue question was cooked up in a joint effort by the offices of Williams and Unley MP David Pisoni.

In parliament, Williams justified the smear by claiming it was in “the public interest” whether ministers adhere to a code of conduct around perceived conflicts. In response, Fox said that she had, in fact, absented herself.

It follows a long period of cynical sledges from the greying opposition shadow on the rising Labor star. In September he asked Attorney General John Rau on four occasions why the government had failed to force the Director of Public Prosecutions to appeal Malcolm Fox’s suspended sentence, when it had done so in an unrelated case seven years earlier.

Williams said the government was guilty of double standards because Labor had intervened in the case of Paul Nemer, a young man who received a suspended sentence for shooting a newsagent in the face. On one occasion, Fox was presiding over question time in her role as deputy speaker.

“Why is it that with the Nemer case the government launched a media campaign and took court action to direct the DPP to appeal the sentence, but in the case of the convicted child s-x offender Malcolm Fox the attorney-general will not use [the] same process?” he mused.

“Did Paul Nemer go to jail because of his offence or did he go to jail because the government of the day, the premier of the day, decided that it would win votes?”

He then added a Clayton’s disclaimer saying his comments had nothing to do with Chloe Fox: “This is about equality before the law.”

University of Adelaide law lecturer and crime expert Allan Perry slammed Williams’ scheming this morning, accusing the MacKillop MP of faulty logic.

“That would mean every politician with a relative who’s been convicted of a driving offense should exclude themselves from debate on road traffic laws, or that any politician with a divorced family member shouldn’t debate family law,” he said.

“It would be different if the relative’s name was still under suppression order, but this case has already been finalised so I can’t see the relevance at all.

“I can’t see how there’s any substantive merit in the assertion that in this case the particular parliamentarian is somehow precluded — if anything one would have thought that her father’s experience would make her better informed about the issues rather than prejudiced in any way.”

Malcolm Fox vigorously maintains his innocence and was set to appeal his conviction until it became clear there was a potential for years of legal turmoil. There was no suggestion whatsoever of political interference in the case, despite its high profile.

Meanwhile, Liberal insiders say Williams’ support base inside the opposition party room is crumbling and he will soon be forced out to make way for fresh blood. He is said to have horrified colleagues with his below-par contributions on the Olympic Dam indenture bill and mishandled others on SA Water, renewable energy and industrial relations.

One Liberal insider was blunt in their assessment of Williams’ competence.

“The majority of MPs have come to the conclusion that Mitch is completely useless,” they said. “He is constantly criticised and is unable to identify even the most basic elements of legislation.”

Williams did not respond to a message left with his office.