Five current NSW Liberal MPs voted for a factional deal to replace sitting members of the Hills Shire Council while they were on the party’s powerful state executive – a decision likely to be central to an anti-corruption probe into fugitive property developer Jean Nassif’s links to Liberal powerbrokers.

Ahead of the launch of the Independent Commission Against Corruption’s Operation Rosny inquiry on Monday, the Herald has obtained documents from the October 2021 meeting of the Liberal state executive at which members voted to install new council candidates in The Hills.

The vote helped spark the ICAC’s probe, after Kellyville MP Ray Williams made an explosive speech to parliament in mid-2022 alleging Nassif had paid “significant funds” to Liberal Party apparatchik Christian Ellis and other senior party members to install new councillors in The Hills Shire Council who would support Nassif’s future development applications.

Then-Liberal premier Dominic Perrottet referred Williams’ claims to the ICAC the following day.

The documents obtained by the Herald confirm for the first time the details of the decision to bypass a preselection and install new councillors.

The motion, authored by then NSW Liberal president Philip Ruddock, states he had been advised of an “agreed position with respect to selecting and endorsing candidates for the 2021 local government elections in The Hills local government area”.

Some of the candidates, the document noted, had not been vetted, while others “did not originally nominate for these positions”.

Voting records for the meeting show while he is listed as the author of the motion, Ruddock himself abstained from voting. Asked why by the Herald, the former attorney-general said: “I have no recollection of those matters.”

But five current MPs who were on the state executive at the time supported it. The group includes four current members of Opposition Leader Kellie Sloane’s frontbench: Chris Rath, James Wallace, Jacqui Munro and Mark Coure. All four are from the dominant moderate faction. The fifth, upper house MP Aileen MacDonald, is from the right.

The five MPs either declined to comment or did not respond to questions by the Herald.

There is no suggestion any of the five MPs were aware of the allegations surrounding the vote at the time.

Instead, senior moderate sources said the vote was part of what had been a long-running agreement between the hard-right and moderate factions that emerged out of the agreement between senior NSW Liberals Matt Kean and Dominic Perrottet.

“As far as we were concerned, it was factional politics as usual in a part of the world that was always really brutal,” one senior moderate who asked to speak on the condition of anonymity to discuss an internal party matter said.

However, many Liberal MPs are privately resigned to the likelihood that the eight-week ICAC inquiry will draw in multiple members of Sloane’s opposition.

Although no MPs have been accused of any wrongdoing, the inquiry has the potential to be hugely damaging for the party even by dragging out a period of messy internal factionalism.

At the same time, senior party members had long raised concerns about Ellis, and his links to Nassif, before the Hills vote.

The Herald has previously revealed senior party members had unsuccessfully sought to stop Ellis’s ascension to the party’s state executive as far back as 2019 because of his links to lobbying firm Beckington. Toplace, Nassif’s company, was registered as a client of Beckington’s from July 2020.

Before his speech to parliament in 2022, Ray Williams, who is a member of the centre-right faction, also raised concerns with then-premier Gladys Berejiklian as early as November 2020.

In a series of text messages, first reported by the ABC and confirmed by the Herald, Williams wrote to Berejiklian urging her to help block attempts by the right faction to move three party branches into the Hills Shire in a bid to control council preselections there.

“It’s completely uncalled for and just an attempt to put [councillors] into the Hills Council who support a particular developer,” Williams wrote at the time, referring to Nassif.

“Raymondo, I’ll call you first thing in the morning Darl,” Berejiklian replied.

Berejiklian initially told Williams she and the then-police minister David Elliott, also a member of the centre-right, were “trying to calm the troops and delay”, but that “so far no one is budging”.

After Williams sent a series of further entreaties, he texted the premier again on the day of the ballot asking whether her representative on the state executive would abstain from the vote.

“I’m not getting involved in this Ray,” she wrote back.

“I’m sick of everyone trying to embroil me in factional issues. I have too much on my plate.”

When Williams said it was “much bigger than factionalism” and involved “corruption by a few on state executive”, Berejiklian said: “You need to report it”.

“I certainly am,” Williams replied.

“Good!!” Berejiklian said.

Ellis is one of 10 persons of interest before the ICAC as part of Operation Rosny, its wide-ranging probe into Nassif’s links to party powerbrokers, councils and the state’s Catholic schools.

The first witness before the public inquiry on Monday will be Michael O’Hara, a publican, lawyer and developer who is a focus of the ICAC’s inquiry. Dylan Whitelaw, a one-time Liberal staffer who has previously been closely associated with many of the figures central to the inquiry, will appear on Tuesday.