Taiwan leader Ma Ying-jeou on Thursday was questioned as a witness in the investigation of a suspected leak of confidential information by the island\'s chief prosecutor, Huang Shyh-ming. Ma went to Taipei\'s local prosecutorial authority on Thursday evening, according to local media reports. Huang is suspected of briefing Ma on information about the investigation of a suspected lobbying case by Wang Jin-pyng, the island\'s chief legislator, before the conclusion of the probe. Huang has been questioned as defendant in the secret leak case, and Jiang Yi-huah, chief of Taiwan\'s administrative authority, and Lo Chih-chiang, a former senior official at Taiwan leader\'s office, were also questioned as witness in this case.