‘This isn’t great’: texts reveal Amy Brown’s reaction to launching of John Barilaro inquiry

The independent inquiry launched by the New South Wales premier, Dominic Perrottet, to probe the appointment of John Barilaro to a lucrative New York trade job doesn’t have the power to examine the actions of government ministers, new documents show.

The latest documents released to the parliament on Wednesday also reveal that the head of Investment NSW, Amy Brown, responded to news an upper house inquiry had been launched into Barilaro’s appointment in June by writing: “this isn’t great”.

The backlash to the New York trade appointment became a major distraction for the Perrottet government after it was announced in late June.

Related: Dominic Perrottet says he should have told John Barilaro not to apply for New York job

While the state’s upper house launched an inquiry, Perrottet commissioned another independent review by former public service commissioner Graeme Head.

Head’s findings are yet to be finalised, but Stuart Ayres last week resigned as deputy Liberal Party leader and from cabinet over concerns that he may have breached the ministerial code of conduct in his interactions with Brown over the appointment. Ayres has denied he breached the code.

At the time Perrottet said Ayres resigned after being shown draft excerpts from Head’s report which were “outside of the terms of reference”.

Documents tabled in the parliament now confirm the former public service commissioner does not have the power to examine ministerial actions.

Head was appointed to run the probe under a section of the Government Services Act, which allows him to use coercive powers to run investigations into public servants or contractors.

Related: Dominic Perrottet’s chief of staff gave ‘strong opinion’ on salary for London trade role, inquiry told

Perrottet has repeatedly said he is waiting for the findings of the Head review – which was originally due on 15 July and then 5 August – before making a formal response to the saga.

However emails released to the parliament make clear Head is not able to examine the actions of ministers, and while Perrottet announced on Tuesday that senior silk Bruce McClintock SC has been appointed to lead a separate review into Ayres, that will focus on his actions alone.

After a request from the premier’s office to the Department of Premier and Cabinet in July for “background” information about the Head inquiry to provide to the media, agency staff had discussed whether to include information about what he was not empowered to do.

• Sign up to receive an email with the top stories from Guardian Australia every morning

“Is there a form of words we can add on background that describes what the inquiry isn’t – ie, it doesn’t have the power to examine ministerial conduct?” a staffer wrote.

A colleague replied that the statement could “emphasise that the inquiry may only inquire into matters relating to the administration of a government sector agency”.

The documents also show that senior public servants were concerned about the separate upper house inquiry into the post.

On 20 June Brown sent a text to Department of Premier and Cabinet secretary, Michael Coutts-Trotter, after the probe was launched in late June with a link to a media article about the inquiry.

“This isn’t great,” she wrote.

Coutts-Trotter responded: “No, but utterly predictable”.

The texts show Brown asked to “talk it through” with Coutts-Trotter. Of hiring Barilaro, she wrote: “technically it was my decision”.

Another earlier exchange between the pair shows Perrottet and the deputy premier, Paul Toole, were said to be “comfortable” with the decision to give Barilaro the job.

Related: ‘Shitshow’ over John Barilaro’s NYC appointment keeps sucking the NSW government in

“FYI – I’ve been told that Premier and DP are comfortable with the appointment of Barilaro as [senior trade commissioner] to the Americas, and requested to get on with formalising the arrangements,” Brown wrote in a message to Coutts-Trotter on 6 May.

“Righto,” he replied.

This comes as the upper house committee probing the appointment released a report on Wednesday that shows the chief commissioner of the state’s Independent Commission Against Corruption had said it was “considering” some of the evidence heard by the inquiry.

The report said Peter Hall QC had written to the committee and told it the watchdog was “considering the information” given to it after Jenny West, the woman first offered the job, gave evidence that Brown had told her the job would be a “present for someone”. Brown has denied saying that.

The report also said the committee has referred a leak of secret evidence, given to the inquiry by Brown, to the parliament’s privileges committee.

The leak, which related to West, was described in the report as “undoubtedly a contempt of parliament”.

The upper house inquiry is set to resume on Friday, when Barilaro will give evidence for a second time.

Perrottet’s office has been approached for comment.