Wattana Muangsuk, a former Pheu Thai MP, has filed a lawsuit against Prayut Chan-o-cha, seeking the lift of the junta chief's order that bans him from going abroad.
He sought a court ruling to revoke the National Council for Peace and Order (NCPO) order No. 21/2557, saying it restricts human rights and breaks international laws, as well as the 2014 interim constitution.
The order, which prohibits 155 people from leaving the kingdom, is discriminatory and arbitrary, he said.
Mr Wattana said the order had a political agenda and violates constitutional monarchy traditions. By restricting the right and liberty to travel, it also breaches human rights principles and the incumbent charter.
Like all Thais, Mr Wattana is well aware his case will go nowhere since the NCPO chief has absolute power over all three branches of government under Section 44 of the interim charter. He made the move for another reason.
"I resort to exercising the right to sue to demonstrate a civilised way to solve problems, not by rolling tanks to seize people's power and then issuing orders arbitrarily," he said.
Mr Wattana also mentioned an act of civil obedience of a Mathayom 6 student at Triam Udom Suksa School as another example.
Nattanan Warintarawet on Monday wrote on her Facebook she had submitted a blank answer sheet for her civic duty examination.
She wrote the blank page was her message to Gen Prayut. "The subject was added to the syllabus by the junta and the content is aimed at instilling in us one-sided discourse while denying diverse opinions, a pillar of democracy".
Mr Wattana, a former social development and human security, industry and commerce minister, was summoned by the army for a session of "attitude adjustment" on June 30 after criticising the army for its handling of protesting pro-democracy Dao Din students.
The army denied it was an attitude-adjustment session but said they just wanted more information about Mr Wattana's request to go to Singapore and Hong Kong.
Mr Wattana also wrote an article on July 17 criticising the junta after he was prohibited from leaving the country for 90 days or until Sept 18.
At the end of the article, he vowed to keep expressing his opinions "because I will not bow to power that does not come from the people".