Activists in Thailand are suing the government for using spyware technology to monitor dissidents, the first such case in the country that they hope will help raise awareness and better protect citizens who are subject to increasing surveillance.

Legal non-profit iLaw said it is preparing a lawsuit against the Thai government for its alleged use of Israeli firm NSO Group’s Pegasus spyware to hack into the mobile phones of at least 30 activists and lawyers in 2020-21. It is the first such case against state surveillance in the nation’s Administrative Court, which tries cases involving government agencies or officials, said Yingcheep Atchanont at iLaw, who is also filing a separate civil lawsuit against NSO.

“It is a difficult case, as we don’t have evidence of who bought the software and who deployed it,” said Yingcheep, 36, whose phone was infected 10 times with Pegasus. “We are also not confident in the judicial system, but it is all we have. Even if we get a verdict saying our rights were violated, that would be very significant,” he said in an interview in his office.

NSO, which did not respond to a request for comment, has said its technology is intended to help catch terrorists, paedophiles and hardened criminals, and is sold to “vetted and legitimate” government clients.