Former Taiwanese president Ma Ying-jeou was yesterday cleared by a Taipei court of defamation and leaking secret information obtained from wiretapping two political opponents.

A Taipei District Court spokesman said the court did not find evidence to convict the 66-year-old.

Lawmaker Ker Chien-ming from the Democratic Progressive Party (DPP) filed the charges against Mr Ma, accusing the Kuomintang (KMT) politician of illegally passing classified information to then Premier Jiang Yi-huah and an aide.

The information was obtained from wiretapped phone conversations between Mr Ker and former KMT Legislative Speaker Wang Jin-pyng, during a 2013 probe into whether Mr Wang - a political rival of Mr Ma - influenced a breach of trust case against Mr Ker in an attempt to benefit the DPP lawmaker.

The now-defunct Special Investigation Department under the Supreme Prosecutors Office later released a transcript of the conversation, in which Mr Wang and Mr Ker appeared to be discussing lobbying senior justice officials to prevent appeals against Mr Ker's acquittal.

Mr Ker and Mr Wang denied any wrongdoing. Mr Ker, 65, later sued Mr Ma, accusing him of violating the Communication Security and Surveillance Act and the Personal Information Protection Act.

Mr Ker claimed the leak had damaged his reputation by implicating him in an alleged case of influence peddling.

Despite yesterday's verdict, Mr Ma still faces a separate lawsuit filed by the government, involving similar charges relating to leaks over the same investigation. He was indicted on March 13.

Mr Ker said he was shocked by yesterday's verdict, which he dismissed as "ignoring the Constitution" and vowed to "appeal to the end".

The KMT hailed the ruling and urged Mr Ker not to appeal to avoid "political name-smearing and wasting judicial resources".

Mr Ma was not present when the verdict was announced. But he appeared in an earlier hearing, where he claimed to have followed proper procedures. Mr Ma had also accused Mr Ker of filing the lawsuit to distract the public from influence- peddling allegations against himself and Mr Wang.

Mr Ma swept to power partly due to his "Mr Clean" image, but has been hit by lawsuits involving charges such as graft, after stepping down as president last year.

He is the third former president in Taiwan to be indicted on criminal charges. His predecessor Chen Shui-bian of the DPP was convicted of corruption and served part of a 20-year sentence - until he was freed on medical parole in 2015. Mr Lee Teng-hui of the KMT was also charged with embezzling state funds during his presidency, but was later acquitted.