He declined to identify them, saying that doing so could attract allegations of unfairness against the anti-graft agency because the next general election is approaching.
“Please allow me not to disclose any names. The next election is approaching, and we are worried about possible impacts,” Niwatchai said, explaining that the commission would be asked why it disclosed names of suspects ahead of an election.
He said the watchdog was not rushing its investigation, but “is working normally on this case”, adding that it was “just a coincidence” that the investigation was occurring as an election approached.
One person under investigation is a member of the ruling coalition, Niwatchai said, declining to name the person.
Those under investigation are from many political parties, but any action by the commission now could impact voting in the upcoming election, he said.
Those under investigation are not considered guilty and the watchdog’s commissioners will decide whether there is enough evidence to indict them, he added.
One suspect is facing charges of severe violation of ethics, the same offence former deputy education minister Kanokwan Vilawan was found guilty of, he added.
The Supreme Court on Wednesday found Kanokwan, a senior figure from the coalition Bhumjaithai Party, guilty of serious ethical misconduct and banned her from running for public office for 10 years.
The verdict was in response to a petition filed by the commission in June. The court accepted the case for trial on August 26 last year and suspended Kanokwan from her duty as deputy education minister.
The commission accused Kanokwan, her father Soonthorn Vilawan, and eight others of illegally occupying about 150 rai of land in Khao Yai National Park.
They occupied three sites with fake title deeds issued two decades ago by Land Department officials.
Niwatchai said on Thursday that the commission had spent about six months investigating Kanokwan’s case.
“It was not difficult or complex. We just had to prove she held the land plot in question and whether it was lawful. After completing the investigation on the two points, we were able to refer the case to the Supreme Court directly, without the help of public prosecutors,” he said.