Gina Rinehart might have won the title of Australia's richest person and most powerful woman for 2015 in the BRW Rich 200 but she lost a significant battle in the courts.

The decision by the NSW Supreme Court to appoint Rinehart's estranged daughter, Bianca Rinehart, to run the family trust is a massive blow on many levels.

It will enable Bianca to review the past conduct of the trust, which Rinehart ran from 1992, and take any action that the trust requires to ensure it receives its full entitlement. Importantly, it will give her ready access to all documents – as ordered by the court.

On another level, the 160-page judgment didn't pull any punches about Rinehart's role as trustee – or her behaviour.

"Mrs Rinehart has demonstrated that she is prepared to go to extraordinary lengths to retain control, directly or indirectly of the trust and that she is capable of exerting enormous pressure and great influence to do so," Justice Paul Brereton said.

He systematically went through the evidence, and left no prisoners. He put the blowtorch on the actions of a number of corporations and high-profile individuals, including Barnaby Joyce.

Joyce might well be ruing the day he sent an unsolicited email using his government address to one of Rinehart's daughters, Hope, who he had never met and who was fighting with her mother.

In response to Joyce's email, Justice Brereton said: "On 11 September, Senator Barnaby Joyce sent Hope an email calculated to dissuade her from continuing the litigation."

His comments were put in the context of Rinehart, "repeatedly, directly, or through her lawyers, or through other influential connections, sought to deter the plaintiffs from prosecuting it, by measures some of which closely approach intimidation".

It prompted Rinehart's estranged son, John Hancock, to say: "It appears Barnaby Joyce fell for her 'manipulation' hook, line and sinker."

PricewaterhouseCoopers' role in the family trust was also put under the spotlight. It was a stinging judgment that could well have ramifications for its reputation as it strikes at the heart of what should be sacrosanct: independence.

"She has demonstrated a willingness and ability to influence an organisation that one would otherwise expect to be independent – PricewaterhouseCoopers – to provide an advice in respect of CGT [capital gains tax] on an assumption about vesting, which was contrary to the advice already obtained, and to 'sanitise' a version of its advice for provision to the beneficiaries."

For Hancock, "PWC has a lot to answer for". What that means, time will tell.

The battle over who would run the trust erupted in September 2011 when the trust, which was set up in 1988 by their grandfather, Lang Hancock, was due to vest, giving the children financial independence.

Three days before, Rinehart wrote a letter to each of her children warning them they would face a capital gains tax bill that would bankrupt them if the trust was allowed to vest.

At the time, Hancock questioned if the beneficiaries would face a tax bill. He later received a private binding ruling from the Australian Tax Office that said no capital gains tax was payable by the beneficiaries on vesting of the trust.

But not before getting emails from one of Rinehart's top lieutenants, Jay Newby, who warned him that he would be hunted down like Christopher Skase unless he ceded control of the family's multibillion-dollar trust to his mother.

In one email, Newby wrote: "Remember what happened to Skase when he tried to escape being brought back to Australia when bankrupt. The government simply doesn't let people off for not paying due taxation."

His threats were based on advice from PWC.

Bianca may have won the battle over who will run the family trust, but it has been a long and tortuous journey that is not over.

There is another legal action about to play out in the Federal Court, which will look at the transfer of Hope Downs and Roy Hill tenements into Hancock Prospecting Pty Ltd (HPPL) and the reduction of the trust's shareholding in HPPL.

Whatever happens, an appeal or a settlement, 2015 is shaping up as a watershed year for Rinehart.

As she battles two of her four children she is also trying to complete her first iron ore mine, Roy Hill, which is scheduled to be completed in the next few months. One thing is for sure, there will be a lot more twists in the Rinehart saga.

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