Businessman Osman Kavala, 62, was arrested in November 2017 and accused of organizing anti-government protests four years earlier. He was charged with making an “attempt to overthrow the government” by organizing and financing an "uprising" with 15 other defendants.
The charge carries a potential life prison sentence. Kavala denied the accusations. Human rights groups said the charge against him, which carries the potential for a life prison sentence, was baseless and aimed at silencing civil society activists.
Ruling in favor of Kavala, the European court, based in Strasbourg, France, cited a "lack of reasonable suspicion that the applicant had committed an offense." The court called on Turkey to “take all necessary measures” to end Kavala's detention "and to secure his immediate release."
There was no immediate response from the Turkish government. The 2013 protests began in 2013 to protect the small Gezi Park in central Istanbul from development but quickly evolved into wider anti-government demonstrations across Turkey.
Police used tear gas and water cannons to disperse mostly peaceful protesters. Kavala founded the Anatolian Culture Foundation, an organization that focuses on cultural and artistic projects for peace and dialogue.
Prosecutors claimed Kavala and the other defendants tried to overthrow the government of Turkish leader Recep Tayyip Erdogan, who was prime minister in 2013 and is now president. The indictment against the defendants also claims that billionaire philanthropist George Soros masterminded the Gezi protests, but does not name him as a suspect.
Erdogan is among the 746 complainants on the indictment and has publicly accused Kavala of financing the protests with Soros' backing.