A 113-year-old courthouse with a towering copper dome near the banks of the Truckee River in Reno, Nevada, was for several days last week the center of a family drama that could in time affect the information and opinion consumption of global millions.

What is at stake could be the fate of one of the most powerful media empires in the world and, in the shape of Fox News in the US, one that has been a driving force behind Donald Trump’s Maga movement just as he seeks to return to the White House.

If Rupert Murdoch, 93, prevails in his legal effort to change voting rights of the family trust to ensure that his chosen successor and conservative-leaning eldest son, Lachlan Murdoch, 53, runs the company after his death, little may change.

According to the Murdoch-owned Wall Street Journal, Murdoch is arguing that “shifting voting control of the trust to Lachlan should be allowed because it is in the best interest of all the beneficiaries, including his other children”.

But if the patriarch loses, the younger brother James Murdoch, in concert with his sisters Prudence and Elizabeth, could force Fox News to move away from the conservative news alignments of their father and brother.

That would be an earthquake in American politics. No other media power in the US has the impact that Fox News has had in the last two decades. It has become a driving force of American conservatism, feared for its power by both Republicans and Democrats. And condemned by many for its conservative bias and numerous show hosts who have become darlings of the US right and powerful players on their own.

Figures such as Sean Hannity are hugely powerful within the Maga world, while the former host Tucker Carlson – now exiled from the station where he rose to power – has withered outside it and been largely unable to recreate the influence he had while broadcasting to Fox’s viewers.

Gaming out the different scenarios at stake in Reno is water cooler talk at Fox News’s midtown New York headquarters, with TV hosts discussing a reposition of their own personal brands if liberal-leaning James wins and opening back-channel communications with him if his father and rival brother prevail.

But despite their immense importance the legal arguments over the Murdoch Family Trust presented within the impenetrable walls of a 1960’s annex court extension in Reno last week are known only to the judge and court staff, Rupert Murdoch, his first and second set of children and an army of lawyers, including Trump’s attorney general William Barr.

“A family trust like the one at issue in this case … is essentially a private legal arrangement,” the Washoe county probate commissioner Edmund J Gorman Jr, wrote in an 18-page recommendation before the parties convened.

The proceedings pit Murdoch, 93, and his chosen successor, Lachlan, against his three more liberal-leaning siblings, Prudence, Elizabeth and James, over future control of Murdoch’s Fox Corp and News Corp through the family’s control of the global empire’s share structure via an irrevocable trust set up in 1999.

James, Elisabeth and Prudence, want the trust to be maintained and oppose Murdoch’s proposed change giving Lachlan control because they would stand to lose voting power.

Yet while Lachlan’s politics are comfortably rightwing and match his father’s, the opposing other siblings have a different world view. James Murdoch even hosted Joe Biden in his home for a fundraiser in 2022 and has endorsed Kamala Harris to beat Trump in 2024.

But it won’t be Fox politics under discussion so much in Reno. Instead, much of that argument will be couched in an examination of US corporate governance conventions that allow for a family to control a business they do not majority own by a so-called dual class structure of shares – in effect the family shares have more power than others.

For example, Rupert Murdoch owns 17% of equity in the media empire and 39% of the voting power.

“The fight for control of the Murdoch empire is only magnified by the dual class structure,” says Charles Elson, a leading authority on US corporate governance issues. “The idea is I am the smartest person in the world and I should run the company as its king. Other shareholders can say we believe you. If that’s a condition of investing, so be it.”

But critics of unequal dual-class voting say the structure weakens executive accountability. “That’s the problem – it basically destroys accountability,” says Elson.

Passing that power on generationally, he adds, only makes it worse. “How do you know the talent is genetic? Simply because they’re the children doesn’t mean they have the same business acumen as the father and it’s not how you pick the leader of a company or a country.”

The Murdoch biographer and antagonist Michael Wolff wrote recently that the late Fox News chair and CEO Roger Ailes told him that the Murdoch sons, Lachlan and James, “are both wannabe little kings”. But that was before open warfare broke out.

“I think they both really believe they were put on earth to show up their father, rather than the reality, which is that they would be mid-level media executives making a quarter million a year and grateful for it, without their old man.”

Earlier this month, the hedge fund Starboard Value sent a letter to shareholders of News Corp, the parent company of the Wall Street Journal and New York Post, calling for the company to eliminate its dual-class share structure.

In the letter, the Starboard CEO, Jeffrey Smith, argued: “This transition of power from Rupert Murdoch to his children has allowed for complicated family dynamics to potentially impact the stability and strategic direction of News Corp.”

Four Murdoch children with voting rights, Smith added, “could be paralyzing to the strategic direction” and, more importantly: “We are not sure why their perspectives should carry greater weight than the views of other shareholders.”

News Corp said it believed its dual-class capital structure “promotes stability and has facilitated the successful implementation of News Corp’s transformational strategy and long-term outperformance for all News Corp stockholders”.

The outcome of the Nevada court battle will not immediately affect the family’s control of the Murdoch empire but could in the fullness of time if Murdoch dies or becomes incapacitated. “If the stock is split up and the family doesn’t get along, the company could face real challenges and it becomes a very bumpy road for the other investors who are not part of the drama.”

But as the caravan of Black SUVs ferried warring Murdochs in and out of court last week, there was at least one certainty, Elson says. While Rupert Murdoch still lives, the company remains firmly under his thumb.

“Rupert Murdoch calls the shots and when he’s gone he really doesn’t have that worry any more. He’s done.”