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 on Monday for the hearing. Last year, he moved to change the terms of his irrevocable family trust in an effort 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 Tuesday of next week. 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 Fox News’s parent company and his News Corp media holdings last autumn. He is arguing that to preserve the commercial value of his businesses 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 New York Times reported. Lachlan succeeded his father as chairman of News Corp in November. He is also executive officer at Fox Corp, home to the 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 attempt 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 New York Times. Irrevocable trusts are typically used to limit estate taxes, among other reasons, and cannot be changed without permission from the beneficiaries or via a court order. The Nevada probate commissioner Edmund J Gorman of the second judicial district court in Reno ruled this summer that Rupert Murdoch could amend the trust if he can show that he is acting in good faith and for the sole benefit of his heirs, the newspaper reported. The court’s ruling notes that Murdoch sought to give Lachlan permanent and exclusive control over his companies because the mogul was worried that a lack of consensus among his children could affect the strategic direction at his companies, including potentially leading to a change in editorial policy and content.