Questions are swirling in Canberra about government contracting and the billions paid to international “consulting” companies doing public servants’ jobs, but it’s unclear whether answers will follow.

Treasury referred alleged legal breaches by accounting giant Pricewaterhouse Coopers (PwC) to the Australian Federal Police for possible criminal charges on Wednesday.

On Thursday, a Greens senator gave AFP commissioner Reece Kershaw a word of warning at a public hearing after he made a bombshell admission that raised questions about a possible perceived conflict of interest.

It concerned a text message he’d received from former NSW police commissioner Mick Fuller. Mr Fuller joined PwC as a partner – after he was cleared of any wrongdoing by an inquiry into two racehorses he part-owned with some well-known Sydneysiders.

Mr Fuller was a neighbour of former prime minister Scott Morrison – who sometimes takes in the former top cop’s bins, it was once reported (and later walked back).

Crossed a line

On Thursday, Mr Kershaw agreed that Mr Fuller was a “friend” and was put on the spot about what that might mean for his  investigation into the firm.

The sheer size of the global accounting firm and the reported $250 million in government contracts it won this year makes this investigation far from ordinary.

Agriculture Minister Murray Watt said he held serious concerns about growing dependent on its outsourcing functions when it was not hiring new staff.

PwC’s array of business lines lend themselves to conflicts of interest, even naturally, critics of the firm have said. It makes billions advising governments on issues of policy, or filling in for shrinking departmental head counts.

But a risk of crossover between its executives advising the Australian government on tax policy and those designing tax minimisation strategies for multinationals apparently became a joint undertaking, redacted emails tabled by the committee show.

There are allegations the company has profited from distributing secret changes to law in Australia.

On Thursday, one senator made the point that it was not clear if the government would succeed in having these problems reviewed independently because PwC’s interests stretch so wide they constantly generate conflicts.

‘It’s the octopus’

“It’s the octopus with tentacles everywhere,” Greens senator David Shoebridge said.

Mr Kershaw was under the gun in Canberra on Thursday, over his connection with Mr Fuller.

Senator Shoebridge quizzed Mr Kershaw about how he could investigate PwC, given he was an associate of Mr Fuller.

Mr Kershaw said he had the utmost confidence the AFP was up to the task of ethically managing interests across a team.

“He’s disappointed with what’s occurred, as in the conduct … of the firm,” Mr Kershaw said.

Mr Kershaw said he hadn’t put in a conflict-of-interest declaration, but did not reveal why.

He said he would take advice on disclosing its contents to the inquiry.

PwC is also the auditor for the federal police – the accountant that signs off on its finances as being legally compliant.

To rip off a bit from the Roman poet, Juvenal: Who will audit the auditors?