Lawyer Haniff Khatri Abdulla said the authorities, especially the Malaysian Anti-Corruption Commission, must investigate the claim and also see if whistleblower protection can be afforded on Twitter user Edisi Siasat who made the allegation.

Haniff said an independent special investigation committee must be formed by the AGC because the department cannot investigate itself due to conflict of interest.

Earlier today, Thomas had denied acting corruptly in handling the case of Tan’s son, who was arrested for drug offences while Thomas was in office.

Twitter user Edisi Siasat, which recently changed its name to Edisi Khas, said Tan’s son was arrested for trafficking a large amount of drugs, and that Thomas had classified the case to require no further action.

Thomas said the allegation that he was corrupt in the context of the Edisi Khas post meant that he was bribed. “Malaysians must rest assured that throughout my professional career and in my personal life, I never bribed anyone. During my stint as a public officer, I never received a bribe,” he said.

Haniff said the whistleblower, the police, prosecutors, and anyone else involved in the case should be investigated.

“Whether or not the allegations are true, seeing how there is an exposé and a denial by Thomas, this must be investigated,” he said in a statement. “Thomas’ quick response is lauded, but it does not mean that his statement puts the case to rest,” he said.