RENO, Nev. >> A probate court in Nevada is set to begin reviewing evidence behind closed doors in a case that could determine who will control Rupert Murdoch’s media empire after his death.

Murdoch, 93, arrived at court Monday for the hearing. Last year, he moved to change the terms of his irrevocable family trust in a bid to ensure that his eldest son, Lachlan, remains in charge of his cadre of newspapers and television networks, including The Wall Street Journal and Fox News Channel, according to reporting by The New York Times based on a sealed court document.

Evidentiary hearings in the case are scheduled to run through Sept. 23. The court has kept the hearings closed to the public and most documents sealed, largely rejecting requests for access by news organizations including The Associated Press.

The trust was originally set up to give equal control over Rupert Murdoch’s businesses to his four oldest children upon his death, according to the Times.

Murdoch stepped down as leader of both Fox News’ parent company and his News Corp. media holdings last fall. He is arguing that to preserve his businesses’ commercial value for all his heirs, the trust must be changed so Lachlan can ensure his newspapers and TV networks continue to have a conservative editorial outlook, the Times reported.

Lachlan succeeded his father as chairman of News Corp. in November. He’s also executive officer at Fox Corp., home to conservative news network Fox News, the Fox broadcast and sports networks, and local TV stations. The media empire spans continents and helped to shape modern American politics.

Rupert Murdoch’s bid to change the trust has pitted him against his other three children named as beneficiaries: James, Elisabeth and Prudence, and they have united to stop their father from revising the trust, according to the Times.

Irrevocable trusts are typically used to limit estate taxes, among other reasons, and can’t be changed without permission from the beneficiaries or via a court order.