Democrat Party politicians look set to petition the Constitutional Court to rule if the government's fresh Section 44 order violates the constitution as they think the order, which parties say amounts to a reset of political parties ahead of the next poll, is illegitimate.
Deputy Democrat Party spokesman Rames Rattanachaweng said Sunday he and Democrat Party deputy leader Nipit Intarasombat had agreed the order may breach Section 26 of the constitution.
Section 26 stipulates that any legislation must not violate the rule of law, or impose unnecessary burdens or restrictions on the freedom of people.
They are considering a legal challenge seeking a court ruling on the matter which is allowed by Section 213 of the charter to protect party members from unfair treatment, Mr Rames said.
He said he and Mr Nipit will initiate the legal challenge personally, not on behalf of the party.
Mr Rames said the NCPO order was illegitimate and causes burdens on party members and is tantamount to a reset of political parties.
Abuse of power is all the more dangerous if those in power refuse to pay heed to others' opinions, he said.
Mr Rames admitted he may be fighting a losing battle as the regime wields absolute power.
Even though there is little chance the legal challenge will succeed, he is prepared to put up a fight, Mr Rames said.
Prime Minister Prayut Chan-o-cha on Friday issued the Section 44 order to address parties' immediate concerns they could not meet the Jan 5 deadline under the new organic law that requires parties to update their memberships and registrations.
However, the order gives new parties a one-month head start over existing ones. Existing parties will not be able to begin the registration process until April 1 next year, while new parties can start forming on March 1.
Existing parties also say that requiring all party members to register again amounts to a "reset" that would open the door for some to defect to new groups.
They suspect the regime is paving the way for a military-backed political party expected to be established to draw members of existing parties to back it and support Gen Prayut and the regime staying in power after an election expected in late 2018.
Mr Nipit earlier said the NCPO order would make life difficult for about 2.8 million members of the party.
Under the order, members of existing parties must produce letters to confirm their membership and pay party fees within 30 days from April 1 or they will lose their status.
Mr Nipit said it is nearly impossible for all party members to do so within that time.
Wiratana Kalayasiri, chief of the Democrat Party's legal team, previously said the fresh order would benefit emerging parties that can be registered from March 1 and can seek the green light from the NCPO to hold meetings.
Also Sunday, Pheu Thai Party heavyweight Chaturon Chaisang lambasted the NCPO order, saying the order is meant to benefit emerging parties while weakening existing parties.
He described the requirement for party members to confirm their membership and pay fees within 30 days as a bid to erode existing parties' membership bases.
Mr Chaturon said the NCPO order shows the regime's power overrides the constitution.
The organic law on political parties went through legislative procedures and its constitutionality was confirmed by the Constitutional Court, but the NCPO issued the order to amend the law quite arbitrarily, he said.
Mr Chaturon went on to say that the order is part of a scheme to pave the way for the NCPO to retain its grip on power.
The reset of political party membership, the order which makes it easy for new parties to set up, and the support for Gen Prayut to return as prime minister after the election all come from the same group of people who pushed for reform before the election which later culminated in the 2014 coup, Mr Chaturon said.
However, NCPO spokesman Piyapong Klinpan rejected accusations the NCPO order has a hidden agenda.
Maj Gen Piyapong said the order partly aims to address the problem relating to the existence of party members as some members previously had not made financial contributions to parties to which they belonged.
Maj Gen Piyapong said the NCPO wanted the public to participate more in the political process and if politicians want to support efforts to improve democracy and create transparency in politics, they should find the order acceptable.
A source at the Internal Security Operations Command said the NCPO commissioned Chulalongkorn University to conduct a secret opinion poll between 2015 and 2017.
Gen Prayut topped the survey of people who should be the prime minister after the election, followed by his deputy Somkid Jatusripitak.
- Earlier report: Democrats fume over NCPO order
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