Former anti-narcotics bureau chief Ng Boon Gay arrived in court at 9.20am on Monday for the last leg of his corruption trial, with his wife Ms Yap Yen Yen by his side.

His lawyer Tan Chee Meng and Deputy Public Prosecutor Tan Ken Hwee will make their closing arguments in the case during the day's hearing.

It wraps up after 14 days of testimony by 10 witnesses. After that, it will be up to District Judge Siva Shanmugam to decide whether or not Ng, 46, had acted corruptly when he received oral sex from former IT executive Cecilia Sue, 36, on four occasions in 2011.

His judgement could have implications for the reading of Singapore's corruption laws. Both prosecution and defence had clashed on the interpretation of the Prevention of Corruption Act in arguing their cases.

Ng is said to have obtained the sexual favours from Ms Sue in exchange for furthering the business interests of her then employers Hitachi Data Systems and Oracle Corp Singapore. The verdict for the case is expected at a later date.