A Taiwanese court yesterday found former president Ma Ying-jeou guilty in a political leaks case, his first conviction in a raft of lawsuits brought against him since he stepped down two years ago.
Ma was sentenced to four months in prison for violating the communication security and surveillance act, said the high court, overturning a lower-court verdict.
Ma said he will appeal the sentence and remains free.
He was also convicted of breaching the personal data protection act and of "using his presidential power not for executing presidential legal duties," the court added.
Under the law any sentence under six months can be paid off with a fine.
The high court found that Ma had attempted to damage the "character and rights" of opposition lawmaker Ker Chien-ming when he leaked confidential information about an ongoing probe associated with Ker.
Investigators had been accused of tapping Ker's phone to acquire the information.
The information that he obtained through his office "should have been kept secret," a statement from the court said.
The leaks controversy sparked a storm in 2013 and saw two top officials resign, while thousands took to the streets to demand Ma step down.
The Democratic Progressive Party, then in opposition, compared the probe to the Watergate scandal in the United States.
The probe revolved around information gained from surveillance on Ker which implicated the then parliamentary speaker, a rival of Ma, in influence peddling.
Last year, the ex-president was cleared of defamation charges and leaking confidential information in two separate cases
Ma was the third ex-president in Taiwan to be indicted on criminal charges.
His predecessor Chen Shui-bian was serving a 20-year sentence for corruption when he was freed on medical parole in 2015.
Lee Teng-hui was charged with embezzling state funds during his 1988-2000 presidency, but was acquitted.