"The appointment of Mr Barilaro as (Senior Trade and Investment Commissioner) to the Americas has all the trademarks of a 'job for the boys' position," Greens MP and committee chair Cate Faehrmann wrote.
"This whole sorry saga has shaken the public's confidence in the integrity of public service recruitment," she said.
The hiring process was flawed and not carried out at a distance from executives, the committee said in its findings on Monday, after months of investigation and a dozen public hearings.
"Despite assurances from senior public servants and ministers that the appointment process was conducted by the public service under a merit-based process, it is clear that the process was flawed and that the executive was not at arm's length from the process."
Former trade minister Stuart Ayres was not at arm's length during the recruitment, and misled the public when appearing at the inquiry, she said.
It was now up to the Legislative Assembly to determine whether Mr Ayers misled the parliament, Ms Faehrmann said.
The decision to change the hiring process from a departmental decision to a ministerial appointment was also made too hastily, causing confusion within the department.
That decision, made by Mr Barilaro, led to a vacancy for the New York City role, which he later applied for.
Premier Dominic Perrottet said the report was politically motivated.
Mr Ayres was cleared of legal wrongdoing in an independent review led by former inspector of the Independent Commission Against Corruption, Bruce McClintock.
"I will listen to an independent former inspector of the ICAC rather than Labor and the Greens," the premier told reporters.
Mr Barilaro's appointment became an ongoing scandal for the government and he relinquished the job before taking up the post.
He has denied any wrongdoing and told the inquiry last year he was vindicated by evidence from other witnesses.
"There's no evidence in this hearing that points to me that I did seek, sought, pressured, public servants in any way. None. Zero," he said.
"You have heard from apolitical public servants who said that I was capable, and a credible candidate, that I would be good at the job."
A separate government-led investigation into the appointment led Mr Ayres to resign as trade minister and deputy Liberal leader over concerns he breached the ministerial code of conduct.
He was later cleared of legal wrongdoing.
One candidate for the New York role, Jenny West, said her job offer was rescinded after she received a briefing note assuring her of her position, signed by former premier Gladys Berejiklian.
She told the inquiry Investment NSW chief executive Amy Brown told her the job would be a "present for someone".
This claim was disputed by Ms Brown, who said the offer was withdrawn after communication broke down between Ms West and the government.
In dissenting statements, government MPs Wes Fang, Scott Farlow and Peter Poulos called the report partisan and "a politically motivated hit job in the lead up to an election".
They cited evidence from members of the hiring panel, who asserted the selection process had been competitive.
