NSW Parliament will receive today an explosive report from the inspector of the Independent Commission Against Corruption, David Levine QC, bucketing ICAC. It will amount to a vote of no confidence in ICAC by the statutory officeholder whose job is to watch over the watchdog.

Levine’s voluminous report, the result of a five-month investigation, covers the failed bid by ICAC to stage public hearings into alleged misconduct by NSW deputy Crown prosecutor Margaret Cunneen SC.

At the commission, the Cunneen probe was called “Operation Hale”.

The High Court of Australia stopped ICAC from launching a corruption inquiry into Cunneen, and the director of public prosecutions subsequently dropped the possibility of any charges being brought against her.

Cunneen continues her role as a senior Crown prosecutor despite the swirling controversy, and she has been voted onto the NSW Bar Council by her supporters.

As the Cunneen controversy swept through the legal fraternity, the media and the political class, the role of ICAC commissioner Megan Latham hit the front pages too.

Her comments at a Bar Association workshop for budding advocates on February 25, 2014, drew hostile fire, particularly her remark that interrogating witnesses at ICAC hearings was “like pulling wings off butterflies”.

As a result, the ICAC inspector’s office received 14 official complaints, including Liberal MPs and coal mining executives who shared bitter experiences at the hands of the commission. A selection of the written complaints were reproduced in Levine’s 2014-15 report to Parliament.

Today’s special report by Levine — to be released after Crikey’s deadline — is unprecedented. No previous ICAC inspector has used the act’s sweeping powers to investigate the commission itself.

One of the inspector’s principal functions is to “deal with complaints of abuse of power, impropriety and other forms of misconduct on the part of the Commission or officers of the Commission”.

Crikey understands that Levine’s investigation has reached the conclusion that misconduct has occurred. It is believed that he has found that search warrants were obtained improperly and illegally enforced, and that some officers did not conduct their inquiries according to the principles of natural justice.

In August, when Levine appeared before Parliament’s joint ICAC committee, he was asked by Liberal MP Damien Tudehope what method he was using to investigate Operation Hale.

Levine replied: “Asking for everything that I can have from the ICAC. And I add that it was been provided, save for the telephone intercepts — if they exist.”

Tudehope, MP for Epping: “I take it you have formed some preliminary views in respect of the manner in which that matter [Operation Hale] was conducted?”

Levine: “Yes.”

Tudehope: “Are you able to share those with us?”

Levine: “No, I would prefer not to.”

Under Section 57C of the ICAC Act, Levine has the power to refer any wrongdoing by anti-corruption staff to the police or the DPP for further action, and he can also “recommend disciplinary action or criminal prosecution against officers of the Commission”.

As the minister responsible for ICAC, Premier Mike Baird will have to respond, and the choices are grim. Does he replace Levine as ICAC inspector or Megan Latham as ICAC commissioner? Or does he call for a root-and-branch renovation of ICAC’s administration?

In the face of Levine’s blistering critique, what he can’t do is nothing.