Christopher Knaus, originally published in the Guardian on 17 October.

Three federal infrastructure department officials and federal MP Angus Taylor separately met with Louise Waterhouse while she lobbied for potentially lucrative changes to her vast landholdings near the Western Sydney airport.

The meetings, which anti-corruption experts say are a “rarity for the average citizen”, have prompted calls for further investigations of the “source and method” through which access was gained to top departmental officials.

Waterhouse’s efforts to secure better road access for her land near Badgerys Creek, a critical change needed to sell or develop the holding, have been widely canvassed before the Independent Commission Against Corruption (Icac) in the past two weeks.

Icac has heard Waterhouse was aided by the disgraced Wagga Wagga MP Daryl Maguire to influence the state government, including senior New South Wales planning officials, who say they were shocked and angry when the pair turned up to a March 2018 briefing and began lobbying them to make favourable changes.

Public documents also show that in October 2017, Waterhouse met separately with federal officials from the infrastructure department to discuss “access to the Northern Road and intersection design changes” and Taylor to give a “project update” and discuss “access to the Northern Road”.

Those changes would have helped Waterhouse either sell the land to a Chinese developer or realise her vision for SmartWest.Sydney – a proposed technology park and business centre that promised to provide a five-star tourism destination and employ 5,600 workers.

The meeting with departmental officials took place on 25 October 2017.

The department would not say whether it brought probity advisers into the meeting, a common practice when discussing planning matters with individuals who stood to gain from them.

“The department met with Ms Waterhouse from SmartWest.Sydney on 25 October 2017 on the department’s premises in Canberra and the meeting was attended by three departmental officials,” the department told Guardian Australia. “No ministers, including minister Taylor, or ministerial representatives were in attendance.

“Ms Waterhouse requested the meeting so she could explain SmartWest.Sydney’s proposal to relocate an intersection planned for the Northern Road realignment around the Western Sydney airport.”

The department said it wrote to Waterhouse two months later to tell her it would not support the proposal to move the intersection.

The changes Waterhouse was lobbying for were not made.

In Icac this week, wiretaps revealed a conversation between Maguire and the NSW premier, Gladys Berejiklian, in November 2017 in which he complained about the problems Waterhouse was having with state and federal authorities.

“They’re all passing the buck,” Maguire said. “So RMS [Roads and Maritime Services] is saying no, no, it’s the federal government’s plan and we have to deliver on it. Federal government’s saying no, no RMS are in charge of the roads.”

Public documents also show Waterhouse met separately with Taylor on two occasions. Taylor was then the assistant cities minister and MP for Hume, an electorate that covers Waterhouse’s property.

The first meeting was in November 2016 for a “project briefing”. The document listed the second meeting as taking place on 26 October 2017, a day after the department meeting for “Project update and access to the Northern Road”, though Taylor’s office was unable to confirm the accuracy of that date.

A spokesman for Taylor, now energy minister, said the meetings took place in Taylor’s capacity as the local MP. But he said Taylor was “not involved in the project nor did he have any decision-making ability over the project”.

“Minister Taylor as the member for Hume often receives project briefings and updates from proponents to ensure he is aware of developments,” the spokesman told Guardian Australia.

He said Taylor and Maguire did not have any communications about the Waterhouse matter. There is no suggestion of any wrongdoing by Taylor or by Waterhouse.

Evidence to Icac on Friday shows that Waterhouse mentioned to Maguire that she intended to communicate with Taylor.

“I’d like to copy some of the people, and certainly send it to Angus Taylor – do you think I should send it to the local member?” Waterhouse asked Maguire in a recorded phone call.

Maguire told her to “shut up” and tell nobody else.

“Tell nobody else now, get all your stuff ready,” he said.

Anthony Whealy, a former NSW supreme court judge and chair of the Centre for Public Integrity, said access to ministers and planning bureaucrats was a “rarity for the average citizen”.

“The right connections, power prestige and money regrettably often play a part in creating a pathway to these hallowed offices,” he said, speaking generally.

“The NSW Icac hearings demonstrate how important it is to have the capacity to investigate the source and method of gaining access to top officials,” Whealy said. “It is only when we can fully investigate meetings of this kind that we can assess their propriety or otherwise.

“Unfortunately in the absence of an effective federal integrity commission, the public is likely to remain in the dark.”