Abbott told parliament’s Crime and Public Integrity Committee earlier this month that Commissioner Bruce Lander presides over a “Star Chamber”-like process, conducts a “trial by ambush” during his investigations, and that he had abused his power.

Lander told the committee this morning that the accusations were offensive, unsubstantiated and wrong.

Abbott had also argued that the rules of evidence should be applied ICAC investigations, to avoid witnesses being “ambushed” into giving evidence that incriminates them.

But Lander said Abbott had fundamentally misunderstood the nature of his office in his comments to the committee. He said he only performs investigations, and does not make findings about criminal conduct, but rather has the power to recommend that the public prosecutor consider corruption charges.

Further, he said that during investigations into criminal behaviour – corruption – he invites every witness to invoke immunity from criminal prosecution for the statements made to the investigation, and that all witnesses had taken up that invitation.

Lander confirmed he had considered reporting Abbott’s behaviour during the ICAC investigation into the Gillman land deal – but that he could not say why he thought that was necessary without revealing submissions from then-Treasurer Tom Koutsantonis. Abbott was acting for Koutsantonis during the investigation.

“I did consider reporting Mr Abbott for unprofessional conduct in the course of the Gillman investigation,” Lander told the committee this morning.

“I could tell the committee why I considered that but I would have to disclose the contents of Mr Koutsantonis’s submissions (to the investigation) to the committee.

“By reason of the legislation, as it currently stands, that wouldn’t be appropriate.”

Lander has long argued that he should be given the power to hold inquiries into serious and systematic misconduct and maladministration in public.

“I am asking for greater scrutiny – why would I do that if I had acted unfairly (in past investigations)?” Lander told the committee today.

The committee has been considering a Liberal Party bill that would allow public hearings – a key promise at the last election.

Lander also denied he had effectively ended the career of former Mental Health Minister Leesa Vlahos by publishing criticisms of her in the final report into maladministration of the Oakden Older Person’s Mental Health Service.

He pointed out the Vlahos announced she would not contest March election two weeks before he published his final report – and that if she believed his investigation had been flawed she could have sought a judicial review into it.

“She could have gone to the Supreme Court to obtain an injunction (to prevent him publishing the report).”

Last week, Ombudsman Wayne Lines told the committee that he was under-resourced to adequately perform his functions – especially in comparison to the ICAC – and that he did not understand the rationale for the Government’s announcement this month that Lander’s office would be given $14.5 million in extra funding to conduct public hearings.

But Lander told the committee this morning Lines had never complained to him that he was under-resourced, and that some of that money was to be allocated to Ombudsman SA.

“He’s never told me in five years that he not sufficiently resourced,” said Lander.

Lines had also questioned the lack of investigations into “big cases of organised corruption” by ICAC.

“I’m not sure why he made that statement,” Lander said this morning, arguing that Lines was in no position to know about his anti-corruption investigations, as they are conducted in private.

“He doesn’t know what I do about corruption,” said Lander.

Committee Chair Dennis Hood apologised to the commissioner for any offence caused by the testimony of Abbott and Lines, but said the committee was not responsible for their statements.

“The committee genuinely regrets some of the statements … have been offensive to you,” said the Liberal MLC.

“We’re not responsible for their remarks.

“On behalf of the committee we’re sincerely sorry for that.”

Koutsantonis – now the Opposition’s spokesperson for Government Accountability and a member of the committee – told Lander today that he had not seen such “conflict” between statutory officers.

He said Lander’s evidence to the committee about how he conducts his investigations was reasonable, but that his concern was about how future commissioners –  potentially lacking Lander’s qualifications and his respect for the rule of law – might conduct investigations.

“There has been procedural fairness (in Lander’s investigations),” said Koutsantonis.

“What I’m concerned about is when you go.”