Future Forward Party (FFP) secretary-general Piyabutr Saengkanokkul on Tuesday vowed to continue political activities even if his party is dissolved and its executives banned from politics.
"If the people in power really believe that eradicating the FFP and banning its leader Thanathorn Juangroongruangkit from politics will prevent us from performing our political roles, I will prove them wrong," he told media.
The FFP would move on and morph into a new party, while he and Mr Thanathorn would continue their political roles outside parliament, said Mr Piyabutr.
On Jan 21, the Constitutional Court will rule on whether to dissolve the FFP over allegations it tried to overthrow the monarchy.
Mr Piyabutr claims the accusers filed the charge "incorrectly" by adding new points to their closing statement.
"They should have known that no new points, witnesses or evidence are allowed to be included in the closing statement," he said.
"The people who handled the closing statement had not studied legal procedure," he added sarcastically.
The court has also accepted a petition filed by the Election Commission (EC) to rule on whether the party should be disbanded for allegedly violating election law by accepting a 191-million-baht campaign loan from Mr Thanathorn.
Mr Piyabutr, a former Thammasat University law lecturer, said he had faith the court would never consider the new details added by the EC in its closing statement.
He said that those convinced the FFP would be dissolved were prejudiced by an opinion that such cases in Thailand were always directed by the political context rather than judged according to the law.
"But if they are right in the end, that will come as proof that decisions to dissolve a political party are based more on political context," he added.
In another development, Pol Lt Co Thanaphat Kittiwongsa, a Future Forward MP for Chanthaburi who was expelled from the party, yesterday formally joined the Palang Pracharath Party.
He was one of 10 MPs who refused to join an opposition walkout to prevent a House meeting on a motion seeking to set up a panel to scrutinise post-coup orders under Section 44 of the interim charter. The presence of the renegade opposition MPs enabled the government to secure the quorum it needed to shoot down the opposition motion.
Pol Lt Co Thanaphat said he had asked his supporters which party he should join after being expelled from the FFP and a vast majority had supported his joining the ruling party.
"I think I made the right decision to join Palang Pracharath to get the country going," he said.