A fresh petition was lodged on Monday with the Election Commission (EC) seeking the disbandment of the ruling Pheu Thai Party and five coalition partners for allegedly allowing themselves to be influenced by former prime minister Thaksin Shinawatra.
The five other parties named in the complaint filed by Nopparut Worachitwutthikul, a former leader of the 2006 White Pigeon group, were Bhumjaithai, United Thai Nation (UTN), Chartthaipattana, Prachachat and Palang Prachrarath (PPRP).
Mr Nopparut's allegation was based on the Aug 14 meeting of key figures from these six parties with Thaksin, father of Pheu Thai Party leader Paetongtarn Shinawatra, at Thaksin's residence after the Constitutional Court ruled to remove Srettha Thavisin from office.
Based on media reports, Thaksin asked key members of the coalition parties to meet him to inform them of the party's decision to nominate Chaikasem Nitisiri as premier. Thaksin reportedly claimed he acted as the father of Ms Paetongtarn who was at that time on a trip overseas.
According to the petition, Thaksin's action could constitute an offence under Sections 28 and 29 of the Political Party Act regarding interference by an outsider in controlling political parties.
The petition also cited Section 21 of the Political Party Act, which requires that party actions be endorsed by the party executives and adhere to the principles of integrity, good governance, and public interest.
It said the offence could result in the dissolution of a political party and claimed that according to the law, the EC is authorised to take such matters to the Constitutional Court for consideration.
"Thaksin's actions gave the impression that he was pulling the strings, and the majority of the public also perceived him to be the owner of the Pheu Thai Party. As Ms Paetongtarn's father, Thaksin was also believed to have influence over her.
"Thaksin often discussed the Pheu Thai Party's policies before the party itself, as if his words were destined to become party resolutions. The Aug 14 meeting could be perceived as a move to form the government," said Mr Nopparut.
He also called on the Department of Probation to clarify the Aug 14 meeting at Thaksin's residence as Thaksin, at that time a convict on parole, was not allowed to engage in politics.
The petition seeking the dissolution of the six parties came as Ms Paetongtarn is preparing to deliver a policy statement to parliament this week before officially starting work.
Next Tuesday, when the cabinet holds its first official meeting, the so-called anti-Thaksin regime groups plan to gather outside Government House.
The Network of Students and People Reforming Thailand, the Dhamma Army, and the Thai People Protecting the Monarchy announced the planned gathering at the weekend. They vowed to continue scrutinising the Pheu Thai-led government and its controversial policies, including the casino-entertainment complex and digital wallet handout schemes.
Pichit Chaimongkol, leader of the Network of Students and People Reforming Thailand, said on Monday the planned gathering was not a rally against the new government.
He said they would submit a petition demanding to find out the progress in investigating the Corrections Department for allegedly giving preferential treatment to Thaksin.
He insisted the group is an organic gathering, not funded by any groups with political interest. He did not rule out the possibility of holding a rally if the government showed no progress because the group's objective was to examine the government's work.
On Monday, Deputy Prime Minister and Interior Minister Anutin Charnvirakul acknowledged the government critics' right to hold a protest but urged them to follow the law.
He also called on them to criticise the government policies based on facts, not speculation, so the government could use them to improve.