Former prime minister Abhisit Vejjajiva and his then-deputy Suthep Thaugsuban have appointed representatives to report to the National Anti-Corruption Commission (NACC) next Tuesday to hear charges against them.
According to NACC secretary-general Sansern Poljiak, Mr Abhisit's representative is expected at NACC headquarters in the morning and Mr Suthep's should arrive in the afternoon.
Afterwards, both men will have 15 days to submit their defence to the NACC. They may do so in person or send in witnesses and documents.
Last week, an NACC sub-panel investigating the April, 2010 crackdown on red-shirt protesters decided to bring charges of malfeasance against both men.
Mr Abhisit and Phra Suthep ordered armed forces to disperse peaceful protesters, resulting in more than 90 deaths and many injuries.
Following the April crackdown, Mr Abhisit and Phra Suthep failed to revise their methods, and launched another deadly crackdown, the NACC ruled.
According to NACC member Vicha Mahakun, who leads a sub-panel investigating the matter, the anti-graft agency found grounds for charges of malfeasance and abuse of authority, which could lead to the pair's impeachment.
Meanwhile, NACC commissioners have delayed their ruling to forward investigation reports into 250 former MPs accused of malfeasance to the National Legislative Assembly (NLA).
The 250 ex-legislators are accused of malfeasance in connection with the 2013 charter amendment attempt to make the Senate fully-elected. The NACC postponed its decision because the NLA is currently considering impeachment charges for 38 former senators over similar accusations.
The NACC team will be able to dedicate its efforts to the case of the 250 ex-legislators once the NLA has made its ruling on the former senators, he said.
Five former legislators also face criminal charges for allegedly amending the charter bill in between readings and swiping absent colleagues' identification cards to vote on their behalf.
The accused are former parliament president Somsak Kiatsuranont; former Nonthaburi MP, Udomdej Rattanasathien; former Sakon Nakhon MP, Narisorn Thongthirach; former Kalasin MP, Khomdej Chaisiwamongkol; and former Maha Sarakham MP, Yutthapong Jaratsathien.