The Gillard government is keeping its distance from besieged independent MP Craig Thomson, raising serious questions about how the crossbencher will pay for his defence in a trial that one industrial law expert expects to continue past the next federal election.

Attorney-General Nicola Roxon and Trade Minister Craig Emerson have both stated Labor won’t fund the independent member for Dobell’s legal costs. So how much cash does Thomson need to defend allegations surrounding his time at the Health Services Union?

The daily cost for legal work — from junior staffers to senior lawyers and partners — runs into the thousands. And that is just for pre-trial preparation. A barrister to represent Thomson in Federal Court is likely to bill at an hourly rate of between $750 and $1000.

Legal costs alone could send Thomson — who earns $190,550 a year as a backbencher — bankrupt, which under section 44 of the constitution would force him from Parliament. The opposition smells blood.

But whether the trial will proceed at all is not certain. Andrew Stewart, a law professor at the University of Adelaide, told Crikey that many of the charges made against Thomson by Fair Work Australia might have exceeded the statute of limitations.

A two-year limitation on workplace claims under the New South Wales Workplace Relations Act means Thomson’s fate hangs on the judgment in the Toyota Materials Handling case which found the statute applied despite the NSW Act being rolled into the Fair Work Act in 2009. That case is under appeal before the Federal Magistrates’ Court. If the findings in the Toyota Materials precedent stands, the FWA’s charges could be dropped. Thomson told the ABC he expected the case to be thrown out, but he didn’t say if he would appeal on grounds the charges are too old.

“That would push proceedings back a long time,” Stewart said of any appeal, suggesting there is no certain path for Thomson’s defence to take, or even that Thomson would choose that avenue of appeal given the costs. Stewart also said it was “highly likely that his case could continue past the next election”.

If the trial goes ahead it’s also not clear if all evidence will need to be presented before the trial commences — that is entirely up to the court. “[It] depends upon the particular Federal Court judge and it also depends upon appeals,” Stewart said. “Some judges like to get things done quicker than others.”

There are 37 alleged breaches that are being brought against Thomson by Fair Work Australia, each with a maximum penalty of $6600. This does not include possible costs the court may seek to impose if Thomson were found guilty. Nor does it include his legal representation.

If the court was to find against Thomson, some estimates have put his total penalties around $250,000. Stewart says this is too simple an equation.

“The charges themselves are not as simple as multiplying $6600 by 37,” he said, adding that if he were found guilty, Thomson should expect to have to pay a lot of money regardless of the outcome. “He is facing fines of tens of thousands of dollars, not including legal costs.”

On Tuesday Crikey revealed that Labor NSW General Secretary Sam Dastyari was anticipating a pre-selection vote in Dobell to take place early next year. Where Thomson’s case will be at that point is uncertain, but the party is keen to move on regardless.