NACC member Prasart Pongsivapai said Mr Somsak and Mr Nikom tried to postpone acknowledging charges and making their clarifications related to their unlawful roles in passing the proposed charter amendment on the composition of the Senate to after February 2.
However, he said that under the NACC regulations, the anti-graft agency must forward the details of the charges to the defendants to study and they have to give clarifications within 15 days which was on January 27 in this case.
He said if the defendants failed to clarify by the deadline, the NACC would assume that they have acknowledged the charges and have no intention to testify to the NACC.
Mr Prasart said as for the 308 former MPs and senators accused of similar charges, they are required to acknowledge the charges by January 15-17 but they will be treated with the same procedure as Mr Somsak and Mr Nikom.
Mr Somsak reportedly told the NACC that he was on a campaign trail while Mr Nikom said he was not in Bangkok so that they could not come to acknowledge the charges but they would do so after the February 2 snap poll.
The NACC concluded on Tuesday that 308 former MPs and senators were guilty of malfeasance after they voted to pass the charter amendment bill that would alter the composition of the Senate.