The Criminal Court has ordered warders to fully protect the rights of Arnon Nampa and other protest leaders currently being held at the Bangkok Remand Prison.
The order was in response to claims by Mr Arnon and fellow protest leaders that they had been harassed by prison officers.
Mr Arnon, Jatupat "Pai" Boonpattararaksa and Panupong "Mike" Jadnok, the two fellow protest co-leaders, claim they were subjected to mistreatment by prison officers on the evening of March 15 and early the following morning.
The protest leaders said they resisted undergoing a Covid-19 test very late in the night despite the insistence of the prison officers.
Mr Arnon claimed prison officers tried to move Mr Jatupat and Mr Panupong from Zone 2 late at night and he feared for their safety.
Mr Arnon, a lawyer already being detained at Bangkok Remand Prison, was joined on the evening of March 15 by Mr Jatupat and Mr Panupong following their transfer from Thon Buri Prison in Bang Bon district.
The trio, who are being held after being indicted on charges related to the youth-led protests, including lese majeste, formally sought the court's protection.
Mr Arnon appeared before the court on Monday to testify to his complaint.
After hearing from both sides, the court ruled that the warders did not take adequate care in handling the situation on the night of March 15 and therefore impinged upon the detainees' rights.
The court ordered the prison officers to be more careful in the execution of their duties and to ensure the detainees' rights are properly protected.
The Human Rights Lawyers Association on Monday gave the court the names of 188 lawyers supporting its request for the detained protest leaders to be released.
The association argued the leaders should be presumed innocent as no verdict on their guilt had yet been given and they should not be treated as prisoners.
