Najib, 71, is serving a six-year jail term for corruption related to the plunder of sovereign wealth fund 1MDB and faces several other cases linked to the financial scandal that led to his defeat in the 2018 elections.

The purported existence of an order by the former king granting him permission to serve the rest of his current sentence at home has been at the centre of his arguments before the Court of Appeal.

A three-member bench ruled 2-1 to grant Najib’s appeal to use the decree to argue his case before the High Court.

“Given the fact that there is no challenge (of the existence of the decree), there is no justification that the order has not been complied with,” said Mohamad Firuz Jaffril, one of the three Court of Appeal judges.

The High Court ruled last year that affidavits supporting Najib’s claim about the document’s existence were inadmissible as evidence because they were hearsay, prompting the former premier to challenge the decision.

But new evidence submitted by Najib’s lawyers showed that “the issue of hearsay can no longer stand,” Firuz said.

“We are therefore minded to allow the appeal,” he added.

Monday’s ruling means that the case will go back to the High Court, where the decree could be introduced as evidence to bolster Najib’s bid to be placed under house arrest.

‘Legal victory for Najib’

Najib was tried and originally sentenced to 12 years’ imprisonment in July 2020 but the sentence was later halved by a pardons board.

Legal expert Goh Cia Yee told AFP that Monday’s ruling is “a legal victory for Najib insofar as he is a step closer to the enforcement of house arrest”.

He suggested that it could take “only months” for the High Court to hear the case.

Najib, however, is also defending himself against graft charges tied to more than $500 million in alleged bribes and several counts of money laundering.