RUGBY AUSTRALIA'S ARGUMENT
Rugby Australia terminated Folau's contract in May after a tribunal found he had breached its code of conduct with an Instagram post telling gay people, along with others "living in sin", that they would go to hell unless they repented.
Many businesses have similar codes of conduct; there is a good chance you agreed to follow one when you signed your own employment contract.
"What Rugby Australia will be arguing is that he's entered into a contract to play for them which includes being covered by the players' code of conduct," Prof Forsyth said.
"The code of conduct imposes obligations which are quite typical of many employers these days, including not engaging in behaviour that is disrespectful or reflects badly on the employer.
"Their code also talks about not being offensive in the way you engage in public debate.
"They'll say that's the contract he entered into, and that by posting the things that he's said about homosexuals and others going to hell, he's breached the code."
You can read Rugby Australia's full code of conduct here, if you're into that sort of thing, but we have pulled out the relevant quotes. By signing his contract, Folau agreed to:
* "Treat everyone equally, fairly and with dignity regardless of gender or gender identity, sexual orientation, ethnicity, cultural or religious background, age or disability. Any form of bullying, harassment or discrimination has no place in rugby."
* "Use social media appropriately. By all means share your positive experiences of rugby but do not use social media as a means to breach any of the expectations or requirements of you as a player contained in this code."
* "Do not otherwise act in a way that may adversely affect or reflect on, or bring you, your team, club, rugby body or rugby into disrepute or discredit."
He also committed not to "make any public comment that would likely be detrimental to the best interests, image and welfare of the game, a team, a club, a competition or union".
Rugby Australia could argue Folau's comments threatened to cost it fans, sponsors and respect, tarnishing the image of the game when he was supposed to serve as its face.
It will certainly point out that CEO Raelene Castle had previously spoken to Folau about his social media use in the wake of an earlier post, back in April of 2018, which again said gay people would go to hell.
"They'll say that he'd been on notice previously about not doing this — it came up last year — and that he persisted in the offending behaviour," Prof Forsyth said.
This kind of dispute is not particularly rare.
"There are lots of employers that have these codes that regulate what employees can do or say, even in their private capacity. And the courts have often upheld those obligations against an employee," he said.
"For example, when an employee pays out a manager on Facebook, even as a private citizen, that can be covered by the employer's quite broadly worded code, and that can form the basis for discipline or dismissal."
The thing that makes this case unique is also a central part of Folau's counterargument — his religion.
ISRAEL FOLAU'S ARGUMENT
Folau has launched his claim under Section 772 of the Fair Work Act, which details all the reasons an employer cannot use to terminate a worker's contract.
Religion is one of them.
So, Folau's argument is quite simple in principle. He will say Rugby Australia sacked him for practising his religion, and therefore the termination was unlawful.
"As a manifestation of Mr Folau's religion, he is compelled to communicate the word of God and the message contained within the Bible, the doing of which he considers to be a loving gesture to others," Folau's legal team said in its application to the Fair Work Commission.
"What he will say is, OK, I entered into that contract and the code, but I'm protected by discrimination law, in this case the Fair Work Act," said Prof Forsyth.
"That protects my right to practise my religion, and you can't dismiss me for exercising my right to practise my religion, to express my religious views."
Football codes and clubs rip up players' contracts all the time over things that happen off the field. Think of the footy player who gets drunk and thumps someone. Those kinds of sackings are rarely controversial.
"Clearly that's private activity. But no doubt that player's contract or code of conduct will say you can't engage in that kind of behaviour, because it reflects badly on the club, and we reserve the right to dismiss you if you do that," Prof Forsyth said.
"What that sportsperson can't fall back on is any other discriminatory ground of dismissal as a protection against the employer getting rid of them. That's the difference here."
One argument has popped up a lot in my conversations with supporters of Folau this week. Many believe that unless Folau's contract specifically forbade him from posting his religious views online, he will almost certainly win.
Prof Forsyth said that was incorrect.
"It would be very unusual for a contract or code to be that specific. They're generally cast in quite wide and broad terms, and that's very deliberate, it's so the employer can catch a whole range of different types of employee behaviour," he said.
"But it is reasonably specific in its application to this case by saying that players have to treat everyone equally and with dignity, regardless of various factors including sexual orientation.
"So I think even if their argument were correct, the code is in my view specific enough to apply to his expression of views.
"The problem is with what's untested. How far does freedom to practise one's religion extend?"
THE UNRESOLVED QUESTION
That conflict, between an employer's right to impose standards of conduct on its workers and an employee's right to religious expression, has never been properly tested in court.
There simply isn't a precedent to tell us how far Folau's rights go in this scenario.
"We don't really have any case law specifically dealing with it, so the question for the court is going to be: is it encompassed within the protection of religion that a person is therefore able to say whatever they think, or quote from the Bible in any way that they like, publicly, in the way that he has done here?" Prof Forsyth said.
"Folau argues he's compelled by being a Christian of the kind that he is, I'm compelled to preach the word of the Bible and the world of the Lord. That's part and parcel of my practising of my religion.
"And unfortunately we just don't know from case law, because there haven't been cases on this, whether the right to practise your religion extends that far."
The best prior examples we can point to are a few cases where employees tried to argue they were protected from political discrimination after airing views contrary to their employer's code of conduct.
"Employers have generally been pretty successful through these codes and policies at encroaching on the private activity of employees," Prof Forsyth said.
"What we're now starting to see, and still hasn't been properly tested yet, is can employees use discrimination law — my right to express my political views my employer might not like, or my right to say what my religion says I should say — as a basis for protecting me from being turfed because I've said what I think?"
You might recall the case of former SBS sport reporter Scott McIntyre, who was fired after posting a series of controversial tweets about Anzac Day in 2015.
McIntyre claimed it was an unlawful termination before eventually settling — like so many others in the same situation.
THE PATH TO A SETTLEMENT
"The problem is these cases keep settling, so we don't get a decision," Prof Forsyth said. "Us employment lawyers are desperate for a ruling."
He said he was "almost as certain as I can be" that Folau and Rugby Australia would end up settling as well.
"Obviously these settlements are always without any acceptance of liability and they're confidential, but you've got to think about the commercial pressures they're under," he said of the sport's governing body.
"How long would they want the circus to go on? From Rugby Australia's point of view, they're looking at the possibility of at least a few more months of this kind of publicity, and it's not very good for their brand, so I think there are commercial reasons why they would want to settle it.
"And then there's also, always in these cases there's the risk they could lose. Which would be even more unhelpful. And he's got a massive compensation claim."
Folau is seeking $10 million in compensation, about half of which is for his lost salary, with the other half covering missed financial opportunities such as sponsorships.
He says his career was cut short at its peak, when his earning power was greatest and he was on the cusp of becoming the Wallabies' highest ever tryscorer.
All of which means defeat for Rugby Australia would be incredibly expensive.
The next step in the case is an upcoming conciliation hearing at the Fair Work Commission.
Prof Forsyth does not expect it to be settled at that point — but don't be surprised if Folau and Rugby Australia reach an agreement just before going to court.