The Yang di-Pertuan Agong’s constitutional power to reduce Najib Abdul Razak’s jail sentence and fine cannot be challenged in court, according to the ex-prime minister’s legal team.

In written submissions by law firm Shafee & Co, they told the Kuala Lumpur High Court that His Majesty’s power is protected by the Federal Constitution.

Najib’s lawyers pointed out that the Malaysian Bar cannot try to...