On February 14, 2015, Sirawit Serithiwat, a student activist from Thammasat University, was arrested along with three other pro-democracy activists, as they held a mock election at the Bangkok Art and Cultural Center, and called for an end to martial law in Thailand.  The following month, on March 16, 2015, Serithiwat and the other activists were reportedly charged with violations of the country’s ban on political activity and holding a public gathering involving more than five people.
The defendants were reportedly released from custody after the charges were filed. As of this report, the charges are pending in the Bangkok Military Court, where the defendants have no right to appeal.  If found guilty, each of the defendants faces possible fines of 20,000 baht (US $625) and a year in prison. 
Scholars at Risk is concerned about the detention and prosecution of students and activists, apparently as a result of nonviolent expression and association – conduct which is expressly protected under international human rights instruments including the Universal Declaration of Human Rights. State officials have a responsibility not to interfere with the rights to freedom of expression and association, so long as such rights are exercised peacefully and responsibly. Imprisonment and prosecution aimed at limiting expression and association undermine academic freedom and democratic society generally. State officials have an obligation to comply with internationally recognized standards of due process, fair trial, free expression and freedom of association.
Sources
http://www.hrw.org/news/2015/03/16/thailand-drop-charges-against-peaceful-critics
http://www.prachatai.com/english/node/4867
http://swe-thai.se/category/wannakiet-chusuwan/