For New South Wales Crown Prosecutor Margaret Cunneen SC, next Tuesday will be the last throw of the dice in her fight to avoid a public cross-examination at the Independent Commission Against Corruption.

On November 18 Cunneen’s legal team will go the state’s most senior legal jurisdiction, the Court of Appeal, to stop the ICAC investigation into allegations she attempted to pervert the course of justice. They will be appealing Supreme Court Justice Clifton Hoeben’s rejection of every argument presented by Cunneen, her son Stephen Wyllie and his girlfriend, Sophia Tilley, to close down the ICAC hearings.

In May this year, Wyllie told Tilley to “pretend to have chest pains” to stop police from breath-testing her at the scene of a car crash. The allegation ICAC wants to investigate is that Wyllie received the advice to fake chest pains during a telephone call to his mother. If proven, the consequences for the high-flying Crown prosecutor and her son could be devastating.

Does anyone imagine that the Appeal Court will overturn the findings of Hoeben, the Chief Judge at Common Law? It doesn’t seem likely. Cunneen’s large array of supporters in the law, politics and the media have been temporarily silenced by Hoeben’s sweeping judgment, but they won’t remain silent for long.

The public discourse over Cunneen’s plight has adopted its own vocabulary: she is facing a “witch-hunt” and being “humiliated” by the ICAC “star chamber”, also called a “kangaroo court”.

The highly charged debate is being fuelled by all those who want ICAC’s powers curbed and its public hearings curtailed. On the surface, bipartisan support for the 25-year-old anti-corruption watchdog remains intact, but senior figures in the three major parties are determined to stop the commission’s “over-reach”.

The Liberal Party has lost two premiers (Nick Greiner and Barry O’Farrell) and endured career-damaging scrutiny of two cabinet ministers, nine state MPs and Senator Arthur Sinodinos; the Nationals haven’t forgiven ICAC for its north coast development probe in the early 1990s, which entangled their leader, the late Wal Murray; and the NSW Labor Party has been bruised and battered by a dozen inquiries involving such colourful figures as cabinet ministers Eddie Obeid, Ian Macdonald, Joe Tripodi and Eric Roozendaal.

So while public support for ICAC has never been higher, the commission’s political masters in Macquarie Street are waiting until after the state election in March to deliver their blow. Plans have already been laid to place ICAC, the Police Integrity Commission and the Ombudsman under single bureaucratic management, e.g. the Justice Department, which is already a sub-branch of the Attorney-General’s Department.

Former premier Bob Carr tried a similar merger after his 2003 election victory, but the scheme was dropped when it failed to gather cabinet support.

While the Cunneen investigation and ICAC’s future are matters of daily speculation, the big question is this: what has ICAC uncovered to lead it to make the State’s Senior Deputy Crown Prosecutor a subject of investigation?

On 29 October Roy Waldon, solicitor to the commission, wrote to Cunneen saying:

“I enclose a summons requiring you to give evidence at the public inquiry. The Commission considers that in respect of this public inquiry you are a person who is substantially and directly interested in the subject matter of the public inquiry.”

Waldon is an ICAC war horse. He has been its in-house solicitor and executive director (legal) almost from its inception. He has sent thousands of summonses to witnesses and sat on thousands of internal committees to consider the commission’s public investigations.

Two days before, on October 27, Commissioner Megan Latham wrote to Cunneen summoning her to appear as a witness in the following matter:

“That on 31 May 2014 Deputy Senior Crown Prosecutor, Margaret Cunneen SC and Stephen Wyllie, with the intention to pervert the course of justice, counselled Sophia Tilley to pretend to have chest pains, and that Sophia Tilley, with the intention of perverting the course of justice, did pretend to have chest pains, to prevent investigating police officers from obtaining evidence of Ms Tilley’s blood alcohol level at the scene of a motor vehicle accident.”

Latham, Waldon and the commission’s operational and legal team are highly qualified professionals who know the ICAC’s powers backwards. They are unlikely to have “over-reached” when they decided to go public with the Cunneen matter.

So the question is this: what do they know that we don’t?

If, and when, the investigation reaches the commission’s hearing room, we shall all hear what they’ve got. And for ICAC’s future to be secured, it had better be good.