Up to 100 members of the National Legislative Assembly (NLA) are ready to vote to impeach former prime minister Yingluck Shinawatra, a highly-placed assembly source said.
It is up to the National Council for Peace and Order (NCPO) to give a signal to at least 32 military officers in the NLA to support the impeachment before Friday's vote, the source said.
The source said that between 80 and 100 NLA members are ready to support the impeachment motion against Ms Yingluck.
These include those from the anti-Thaksin Group of 40 Senators, academics, civil servants and business groups, the source said.
The impeachment requires three-fifths of NLA members' support, or 132 votes.
All 220 NLA members were handpicked by the NCPO and more than 100 of them are former or active military officers.
"If the captain does nothing and lets his crew members act on their own, the impeachment bid will fail," the source said, referring to Gen Prayut and the NLA.
The source said several NLA members who have ties with ex-premier Thaksin Shinawatra are expected to vote not to impeach.
If the impeachment fails, the NLA will lose credibility and "the boat and all those on board — the NCPO, the government, the NLA and the National Reform Council — will be shipwrecked", the source said.
The source said many NLA members see no reason to let Ms Yingluck off the hook.
They believe the case against her is backed up by strong evidence under the National Anti-Corruption Act and the law governing national administration regulations.
Regarding the impeachment cases against former House speaker Somsak Kiatsuranon and ex-Senate speaker Nikhom Wairatpanich, the source said that about 70 military officers sitting on the NLA have made it clear they do not want to impeach the pair.
This is because the legal basis for their impeachment is weak, the source said. The 2007 constitution which the National Anti-Corruption Commission (NACC) cited as the basis for their impeachment no longer exists, the source said.
The NACC petitioned the NLA to impeach Mr Somsak and Mr Nikhom over their role in chairing a joint House-Senate debate on a charter amendment bill to make the Senate a fully-elected chamber.
The NACC accuses the pair of malfeasance in office, abuse of power and gross violation of ethical conduct in accordance with sections 270 and 291 of the 2007 constitution.
NLA member Thaweesak Suthakawatin yesterday said he did not think Gen Prayut was sending any signals to NLA members on how to vote, referring to the PM's comment on Monday that he would not reconcile with anyone who breaks the law.
Gen Prayut was urging NLA members to take a sensible course of action when voting on the impeachment motion, Mr Thaweesak said.
Ms Yingluck's failure to show up last Friday to answer questions from an inquiry committee set up by the NLA will have a bearing on the vote, he said.
The NLA will have to take responsibility for the outcome of the vote, whichever way it goes, he added.
Ms Yingluck faces impeachment for alleged dereliction of duty in the rice-pledging scheme.
She chaired the National Rice Policy Committee when she was premier.
NCPO spokesman Winthai Suwaree said yesterday the NCPO had briefed the cabinet on the security situation, which remains normal.