The process will determine if a civil case is mounted.
Wissanu explained that the case was divided into three parts.
The first part, the impeachment process, has already been completed by the Office of the National Anti-Corruption Commission and the National Legislative Assembly.
The second part is the criminal case, which has been submitted to the Supreme Court’s Criminal Division for Political Officer Holders.
The third part is the civil trial.
Wissanu said that the authorities placed great emphasis on treating the case with fairness in accordance with the rule of law.
He said that ministerial regulations contained in the Act covering offences by state officials would be applied.
Everyone would be afforded a proper defence, he said.
Wissanu said that two fact-finding committees had been established.
This first committee is investigating former Prime Minister Yingluck Shinawatra – the chairwoman of the National Rice Policy Committee – and the second committee is probing six Ministry of Commerce officials.
The investigation process would be completed by the end of September, Wissanu said, adding that the investigation report would be submitted to Prime Minister Prayut Chan-o-cha.
He said the case file would be submitted to the committee on civil liability and compensation, which had until February 2017 to work on it before the statute of limitations on the case expired.
He believed, however, that the entire process would be completed early next year.
He added that those found guilty would have to pay compensation, but would not face prosecution.