Rugby: Disgraced Wallabies star Israel Folau's explosive letter to Rugby Australia leaked

Defiant former Wallabies star Israel Folau has penned a scathing letter to Rugby Australia, demanding answers as to how confidential information from his code of conduct hearing was "leaked" to the media.

The 30-year-old fullback had his lucrative $4 million contract with RA terminated last month after being found guilty of a high-level breach of the organisation's code of conduct for his homophobic social media posts, including an Instagram post in April that condemned drunks, homosexuals, adulterers, liars, fornicators, thieves, atheists and idolaters to hell.

Folau decided not to appeal through RA's internal channels, saying that he feared he would receive unfair treatment during the process.

He has, however, launched legal proceedings with the Fair Work Commission against RA and the Waratahs seeking damages - reportedly to the tune of $10 million.

In the letter, Folau accuses RA - including Kiwi chief executive Raelene Castle - of dishonesty and demands an explanation as to how confidential information became public.

"I would like an explanation as to why recent detailed media articles about me have revealed aspects of confidential sworn testimony and witness statements from the Rugby Australia Code of Conduct Tribunal.

"This is blatantly unfair. As you know, the Tribunal hearing must be closed and private, and Rugby Australia was obliged to keep all information confidential," Folau wrote.

Israel Folau has taken Rugby Australia to task for leaking 'confidential' information...in a letter that has been leaked. Photo / Facebook

"I would like to know why Rugby Australia has not managed to maintain the integrity of its processes and ensure that information was kept private and confidential.

"I feel like the way the hearing and related matters have been described in the media has been unfair and misleading. For example, I am not 'sick of rugby' and whoever told the media that I am is telling lies.

"Another example is the way the media has been told that your 'expectations' were made clear to me by Ms Castle. We all know that that is far from the truth."

Folau insists the termination of his contract constitutes discrimination on the grounds of his religious beliefs.

Rugby Australia chief executive Raelene Castle and NSW Rugby CEO Andrew Hore. Photo / Getty

"I know this may be difficult for some to understand, but I am nothing if I am unable to share the word of the Bible with my fellow man.

"And yet the position of Rugby Australia is that I must be banned for life for doing so.

"Finally, as I believe your termination of my employment was unlawful, I wanted to inform you that have made an application to the Fair Work Commission in the hope that this injustice may be reversed."

On Thursday, Folau's younger brother John was granted immediate release by the Waratahs after requesting to leave in protest over the sacking of the 62-test Wallabies veteran.

John Folau, 24, has struggled with "divided loyalties", according to the team.

He has not played a game for the Waratahs since joining the team just before the start of the season and has been on leave for weeks.