Victorian Greens leader Greg Barber has fronted the Supreme Court in a precedent-setting case with huge ramifications for journalists and anyone concerned with transparency in government.

Barber, a game theory aficionado who has pleased political scribes with his commitment to hard data and spreadsheets, is taking on Ted Baillieu over the Liberal government’s failure to release a secret 2011 Deloitte review into the dubious Myki public transport ticketing system that apparently justified its rollout. Debbie Mortimer SC has been enlisted to argue Barber’s case.

The Northern Metro MP has been scratching around to fund the case before Justice Karin Emerton that, according to legal experts, could have far-reaching ramifications for constitutional law — not just in Victoria but across the nation.

In his letter rejecting the Legislative Council’s Myki request last year, Treasurer Kim Wells argued the government did not have to produce the review because the report had simply been discussed by cabinet. It was a curious decision given the disaster-prone $1.4 billion project was considered the brainchild of the previous Labor government.

The case could also help answer a broader question in the abstract — what are the rights of Parliament?

But that’s if the lightning rod isn’t snuffed out first on jurisdictional grounds. Barber is seeking a declaration from the court that the Council has the power to order production of documents prepared for cabinet — and failing that, a narrower claim over documents prepared by an independent contractor — such as Deloitte — for cabinet.

“Without transparency we cannot have a functioning democracy,” Barber told reporters on the Supreme Court steps, citing a treasure trove of other documents on issues like the desalination plan that could be turned up by a successful decision.

Records of cabinet deliberations — which should on most arguments be kept secret — are not at issue. Rather, it is “external reports” like the Myki review that are prepared by contractors and then barred from release simply because they’ve come before cabinet.

This morning the government called for the case to be thrown out because it fails to meet the threshold of “justiciability” — that is, there is no “live” cause of action in the “entirely hypothetical” legal excursion. Barber, it further argued, “wanted to take it out of the Council and put it in the hands of the Court”.

It maintained the court doesn’t have the power to intervene in the workings of the Council and so a claim for a “bare declaration” as to the Parliament’s powers could not hold.

Monash University constitutional law expert Greg Taylor, who appeared at a Castan Centre for Human Rights Law forum discussing the case last week, says the court needs to transcend the “two extremes” in the debate: the idea the Council can call for any document and have it published, or that the Executive can deem anything a “cabinet document” and keep it hidden from prying eyes.

Taylor suggests the Victorian parliament should follow NSW’s path and appoint an independent arbiter, such as an ex-judge, to determine whether a claim to secrecy by the government is a legitimate or not.

Taylor, who has previously held forth on former attorney-general Rob Hulls’ eagerness to use weird precedents when squirming out of requests during the Brumby era, told Crikey that Barber’s was a “precedent-setting case on two fronts” — in that he was asking the court to step in and broadly declare the rights of Parliament as it believes them to be. In a “substantive sense” it will help decide if the parliament has the right to demand documents even though they might have some connection with cabinet.

The Victorian Parliament’s broad rights are in fact much greater than the oft-derided freedom of information process, which contains easy exemptions for cabinet documents.

There are some interesting legal precedents. In the 1996 case of Egan v Willis, that went all the way to the High Court, NSW Labor treasurer Michael Egan refused to cough up documents relating to a proposed goldmine to a hostile upper house. University of Sydney constitutional law expert Anne Twomey, at the time a government adviser, recalls looking on as Egan was “assaulted” and chucked out on the street by the Black Rod in order to get the case before the courts.

In a memorable Macquarie Street curbside presser, Egan claimed he had been “intimidated and terrified” by “the big, burly Usher of the Black Rod”, who had approached the treasurer “in a threatening way with his black rod”.

The High Court dismissed Egan’s appeal, finding the Council could demand documents but that definition of the power is determined by the mores of the time.In Egan v Chadwick, the NSW Court of Appeal held that it did not have the power to order the production of cabinet documents, although there was some dispute over what these documents entailed. Justice Meagher argued it applied to documents generally, while Justice  Spigelman said that documents revealing the deliberations of cabinet should be excised, while another basket “may or may not” lie beyond the Council’s power (there’s a nice summary of both cases on the APH website).

But the NSW experience differs from Victoria and other states in two important ways: the Parliament has a restricted right to cabinet documents, partly because there is no direct reference in its constitution to the privileges and immunities of the UK House of Commons as it stood in 1855, as in Victoria.

And in court this morning, the government argued that because there was no “trespass” in the Barber case that brought the Egan v Willis case into the general law, it was inappropriate for the court to intervene in the parliament’s processes.

Twomey agrees the case is likely to be struck out because the “cause of action” is not substantive enough — it is widely accepted courts only get involved when they have to resolve a question of external law.

“This is probably going to fizzle … most likely it will die on these procedural grounds before it ever gets to the substantive action,” she said. “The main problem is the Legislative Council itself has not taken any further action” — that is, it had failed to challenge Wells’ follow-up letter refusing access to the Myki report.

“There is no proper cause of action going on here,” she said. “The Victorian government has good grounds for this. There is a tradition of the courts not getting involved in the internal proceedings of parliament.”

If Justice Emerton decides that Barber v The State of Victoria is “on foot”, then a new date will be set down for the case to be tried, probably before the end of the year.

Barber hosted a garage sale in Brunswick on Saturday that raised about $800 for the venture. But with costs expected to run into the tens of thousands of dollars the quest could take a severe toll on his wallet — that presumably also holds the Greens leader’s flawed Myki.