The Pheu Thai Party has announced its support for amendments to the country's lese majeste and sedition laws, while the ruling Palang Pracharath and Democrat parties remain firmly opposed to any changes to the royal defamation law.
The main opposition party said in a statement on Sunday it will ask parliament to discuss amendments to sections 112 and 116 of the Criminal Code.
The announcement came after the party elected a new executive board following a general assembly of party members in Khon Kaen last week. The party also named Paethongtan Shinawatra, the youngest daughter of fugitive ex-prime minister Thaksin Shinawatra, as its chief adviser on participation and innovation.
The move coincided with the start of a campaign calling for the release of co-leaders and members of the anti-government protest group, Ratsadon, who are currently detained under a slew of charges that include violating the royal defamation law.
Panusaya "Rung" Sithijirawattanakul, a Ratsadon co-leader and who is herself accused of lese majeste, submitted 28,426 names of people who signed up to the group's online petition demanding the unconditional release of the young protesters, to Prime Minister Prayut Chan-o-cha.
She insisted the protesters have the right not to be detained for expressing their ideas and thoughts.
Ms Panusaya described the way authorities have treated protesters who expressed a different opinion to theirs as "shameful".
On Monday, Pheu Thai said that in addition to agreeing to back amendments to the two sections, it wanted to scrutinise the way law enforcement officials, including police officers and public prosecutors, applied the laws.
The party is in favour of correcting laws and regulations which are unfair so that prisoners of conscience can be freed and no other individuals face the same fate, the statement said.
According to Pheu Thai, some people are concerned about the increasing number of people charged with violating sections 112 and 116 of the Criminal Code since the emergency decree was announced at the onset of the Covid-19 pandemic last year. The party said the sections are being enforced in a way that undermines the rule of law and harms public trust in the justice system.
Meanwhile, Sira Jenjaka, a Palang Pracharath Party (PPRP) MP for Bangkok, said scores of people have also signed up for a campaign to oppose changes to any laws concerning the monarchy.
"Pheu Thai needs to explain what its intentions are," the MP said.