Thailand's progressive Move Forward Party, which won most seats at the last election, faces a crunch court ruling Wednesday on the legality of its campaign pledge to reform the kingdom's tough royal defamation laws.
MFP upended Thailand's political order by coming first in the general election last May, but its promises to reform the military, business monopolies and lese-majeste laws spooked the kingdom's powerful conservative elite.
Leader Pita Limjaroenrat was blocked from becoming prime minister and MFP was shut out of the governing coalition.
Pita returned last week to parliament after he was cleared of breaching election laws in a case that could have seen him barred from politics.
Now the Constitutional Court is scrutinising the party's campaign promise to reform Thailand's strict laws protecting King Maha Vajiralongkorn and his close family from insult.
The court is expected to issue a ruling around 2:00 pm (0700) on a petition arguing the MFP policy amounted to an attempt to overthrow Thailand's monarchy.
The court is not expected to order the party's dissolution, but could tell it to drop its lese-majeste reform policy.
Thanathorn Juangroongruangkit, the former leader of Future Forward Party -- an MFP forerunner dissolved by court order -- said lese-majeste should be up for discussion.
"The law is not a fax paper sent from God. It's written by human hands, therefore people can amend it," Thanathorn told reporters on Wednesday.
"If the lawmakers cannot amend the laws, I think something is wrong in the country."
The lese-majeste law is intended to protect the king -- a revered, semi-divine figure in Thai society -- from insult, and those breaking it can face up to 15 years in jail per offence.
But critics say the legislation has been interpreted so broadly in recent years as to shield the the royal family from any kind of criticism or mockery.
Earlier this month a man was sentenced to 50 years in prison for a series of Facebook posts deemed insulting to the monarchy.
And in March last year a man was jailed for two years for selling satirical calendars featuring rubber ducks that a court said defamed the king.
The yellow bath toys were an unexpected symbol of mass youth-led street protests that shook Bangkok in 2020.
Reform of the lese-majeste law, known in Thailand as 112 after the relevant section of the criminal code, was a major theme of the demonstrations, which featured unprecedented public criticism of the royal family.
More than 250 people have faced royal insult charges in the wake of the protests, according to Thai Lawyers for Human Rights, a legal group that handles many cases.
They include senior protest leaders and at least one elected MP.
