The inspector of the ICAC, David Levine, has called for an end to the corruption watchdog's public hearings, arguing they lead to people's reputations being trashed.

Key points: Report assessed whether ICAC powers "just and fair"

Report assessed whether ICAC powers "just and fair" Ability for individuals to have ICAC records expunged recommended

Ability for individuals to have ICAC records expunged recommended Inspector involved in public dispute with Commissioner

Inspector involved in public dispute with Commissioner More powers of oversight over ICAC called for

Mr Levine's report was commissioned in the wake of the High Court's ruling that the ICAC did not have the power to pursue an investigation into crown prosecutor Margaret Cunneen.

He was asked by the New South Wales Premier to assess the ICAC's conduct and whether its powers and the way they were exercised were consistent with justice and fairness.

If adopted, the main recommendation of his report, which was tabled today, would be a seismic shift in the way the ICAC conducts its business.

"I have come to the view that proceedings of the ICAC should be in private," Mr Levine wrote.

"That does not prevent the exposure of found conduct at the end of the investigation and the referral to prosecuting authorities.

"It will prevent the undeserved trashing of reputations and will still permit a proper focus and a fairly managed forensic process, without the distraction of temptation for flamboyance or theatre."

The ICAC issued a statement in response that said the inspector did not undertake any consultation with the commission on "any of the important issues canvassed in the report".

It said the principal recommendation was contrary to the recommendations made by an independent review in 2005, and more recently, the Independent Panel Review in 2015.

The ICAC spokeswoman said the commission agreed with the 2015 review's assessment which found public inquiries "serve as an important role in the disclosure of corrupt conduct [and] in disclosing the ICAC's investigative processes".

Former ICAC commissioner David Ipp QC said the recommendation would undermine the ICAC's power and purpose.

"I disagree fundamentally with the Inspector," he said.

"This is a means of defanging ICAC. Its main function is exposing corruption; this cannot be done without public hearings."

Public hearings 'shine a spotlight on corruption'

Anthony Whealy QC, a former ICAC commissioner, said the recommendation was completely out of step with other ICAC jurisdictions.

Former ICAC commissioner Anthony Whealy QC has spoken out against plans to put an end to public hearings. ( AAP: Paul Miller, file photo )

"One of the advantages of a public hearing, not only does it shine a spotlight on possible corrupt behaviour, it means the public know what's going on.

"And there are many people out there in the public arena who will have information that's very important to the investigation.

"If you conduct the investigation behind closed doors, they never hear of it and the valuable information they have will be lost."

Mr Levine also recommended that the Government consider legislation that would provide an "exoneration protocol", which would allow individuals to apply to the Supreme Court to have the records of the ICAC expunged.

The ICAC said "this recommendation ignores the basis upon which corrupt conduct findings are made under the ICAC Act. It also ignores relevant case law".

An independent panel was also commissioned by the Premier to examine the ICAC's powers, but when it issued its report last year it did not recommend any changes to the watchdog's ability to hold public hearings.

Since being commissioned to write the report, Mr Levine has been involved in a bitter public dispute with the ICAC commissioner Megan Latham.

Last year, he wrote a scathing report where he described the ICAC's investigation into Ms Cunneen as the "low point" in the organisation's history and accused Ms Latham of overseeing an operation that at times constituted "unjust, oppressive maladministration".

During a series of parliamentary hearings into that report, Ms Latham accused Mr Levine of bias and a lack of professional respect.

Inspector wants more powers over ICAC

In his report today Mr Levine also advocated for his office to be given more powers of oversight over the ICAC.

"The ICAC will be taken more seriously if it is known that the oversight of it is a serious business: the reputation of this state can only be improved by this outcome," Mr Levine said.

Mr Levine also recommended that people should be informed about the nature of the allegations or complaint being investigated before a compulsory examination or inquiry begins, unless there are exceptional circumstances.

The Premier issued a statement welcoming the inspector's report.

"This Government has zero tolerance for corruption in NSW, which means a robust ICAC," Mike Baird said in the statement.

"But we also need to ensure that ICAC uses it extraordinary powers responsibly.

"As I have previously stated, the inspector's report will now be considered by the bipartisan committee on the ICAC. This matter should be above politics."