Prime Minister Najib Abdul Razak has told the High Court that he had no role in police investigations against the Malaysian Anti-Corruption Commission (MACC) that were initiated last year.

In his statement of defence that was filed yesterday against a suit former premier Dr Mahathir Mohamad and two others, Najib also denied influencing attorney-general Mohamed Apandi Ali.

In January, Mohamed Apandi had concluded that the three investigations papers submitted by the MACC on their probe against Najib could not be brought to court for criminal proceedings.

On the sacking of Muhyiddin Yassin as deputy prime minister, Najib argued that the plaintiffs must prove that the removal was related to criticisms of Putrajaya's handling of 1MDB.

"The removal of Muhyiddin as DPM is an exercise of royal prerogative under Article 43(5) of the Federal Constitution acting on the advice of the PM and such act is, again not an act of the defendant (Najib) in the exercise of his duties as an alleged public officer or as an alleged fiduciary," he said.

Mahathir, Anina Saadudin and Khairuddin Abu Hassan had sued Najib in March for breach of fiduciary duty and misfeasance in public office.

Najib also denied interfering, or continuously interfering, with the due process of the law by using his position as a public officer to ensure the authorities carried out the necessary alleged investigations of impropriety or misconduct against him.

"I further contend that I have not abused my position as PM, finance minister, BN chairperson and Umno president to further the alleged corrupt practices.

"The defendant further contends that as BN chairperson and Umno president, he does not exercise duties of a public officer nor does he act as alleged by the plaintiffs."

Hence, Najib said the suit brought by the three did not fulfill the ingredients of tort of misfeasance in public office and the alleged tort of breach of fiduciary duty in public office.

Najib also denied he had a hand in suspending The Edge or banning its sister publication The Malaysian Insider.

He said Home Minister Ahmad Zahid Hamidi took action against The Edge under the Printing Presses and Publications Act 1984.

“Hence, it does not concern or relate to me in the exercise of my duty as an alleged public officer or as an alleged fiduciary,” he said.

Mahathir's right to withdraw support

Najib said Mahathir had the right to withdraw support for him, but added that this did not give rise to a cause of action of misfeasance in public office or tort of fiduciaries in public office.

He said the former premier's presence at the Bersih rally last year did not give rise to a cause of action.

On the investigations against Mahathir, Najib said that the police were entitled under the law to question the former premier if there was an offence of criminal defamation.

Najib said police action against Mahathir was not a result of him exercising his duties as a public officer or breaching his fiduciary duty.

“Mahathir is entitled to voice his criticisms on his web blog and that does not give rise to cause of action of misfeasance in public office and tort of breach of fiduciaries in public office,” he said.

Najib further denied being responsible for the actions taken against former Batu Kawan Umno division leader Khairuddin Abu Hassan (photo), who is the second plaintiff in the suit.

Khairuddin was arrested last year under the Security Offences (Special Measures) Act 2012 and charged under Section 124L of the Penal Code for attempting to sabotage Malaysia's banking and financial systems.

Najib added that he was not responsible for the travel ban imposed on Khairuddin.

On the third plaintiff, Anina Saadudin, who was expelled from Umno, Najib said she had agreed to the party constitution and was contractually duty-bound to its provisions.

“This does not give rise to a cause of action against me for an action of misfeasance in public office and alleged tort of breach of fiduciaries in public office.

“I will therefore contend that Anina has no cause of action to the two torts referred above,” he said.

He challenged Mahathir, Khairuddin and Anina to show they had suffered any losses as a result of him exercising his power as a public officer, and that such acts were done with malice.

Challenge on Muhyiddin

Najib also denied Muhyiddin's claims that he had been prevented from performing his duties in BN or as the Umno deputy president.

The prime minister said they were not his acts as a public officer.

“These alleged acts, if any which are denied, give rise if at all, to a cause of action by Muhyiddin against Umno and BN and not me,” Najib said in his defence.

Najib also denied derailing the authorities' investigation into the money 1MDB and SRC International allegedly channeled into his accounts.

The statement of defence was filed by Najib's solicitors from the firm of Hafarizam, Wan Aisha and Mubarak.