Two of NSW Premier Dominic Perrottet's brothers have ignored a summons to front a parliamentary inquiry examining the influence of property developers on a council in Sydney's northwest.
Charles and Jean-Claude Perrottet were called to appear before the inquiry into Hills Shire Council beginning on Wednesday but have failed to respond to invitations and official summons.
The inquiry follows Liberal MP Ray Williams last year using parliamentary privilege to allege Christian Ellis and other unnamed senior members of his own party were paid to install new councillors who would be friendly to high-flying Sydney developer Jean Nassif.
Asked on Saturday if he had spoken to his brothers regarding their apparent refusal to front the inquiry, the premier replied bluntly, "no".
"It's a matter for the upper-house inquiry ... I'm not going into these details," Mr Perrottet said.
Committee chair and Greens MP Sue Higginson said the inquiry had taken the serious step of summoning the Perrottet brothers, Mr Ellis and Hills Shire councillor Virginia Ellis, Mr Ellis's mother, but all four appeared to be "deliberately avoiding accepting service of the summons".
"This appears to be a calculated and coordinated attempt to avoid scrutiny by the NSW parliament," she said.
Mr Nassif, who is now in Lebanon, wrote to the committee last week asking for hearings to be postponed.
In his letter, he denied paying anyone to "undertake any actions regarding pre-selections or any similar actions", adding he had not met with any current councillors and he was unaware of their views on his developments.
But senior Labor MP Penny Sharpe said the allegations raised by Mr Williams, which have also been referred to the Independent Commission Against Corruption, were very serious and called on the Perrottets and the Ellises to front the inquiry.
"They can clear this up today by coming forward and saying they'll show up... (for) the public hearings," she told reporters.
"People deserve to know this before the elections".
The controversy over the Hill Shire Council hearing comes as the government announced an $11 million grant to North Sydney Oval as part of its commitment to women's sports.
The premier also promised a 3.3 km elevated high line transforming the rail corridor from Lavender Bay to Waverton into a new public space with sweeping views of Sydney harbour if he was re-elected.