The first hearing in the trial of a Turkish environmental activist, who faces charges stemming from a peaceful protest against new coal mining near her home, will begin on April 27. Meanwhile, the court is holding her in detention to prevent her from protesting.

The detained activist, 26-year-old Esra Işık, has been campaigning against a controversial 2019 government decision to cut down olive groves near her family’s home in Muğla, Western Türkiye, to make way for coal mining. Her detention, and that of two others who condemned her arrest, raises concerns about whether Türkiye will fulfill its responsibilities as co-host of the United Nations climate summit, known as COP31, scheduled for November.

After her March 30 arrest, a court ordered Işık be held in pretrial detention, citing a risk that she would protest visits by the court-appointed experts to the contested land—which is subject to an urgent expropriation process—and unduly exert pressure on them. Such a preemptive jailing for a potential intent to protest is not lawful under Turkish or international law.

Başaran Aksu, a trade unionist from the mining union Maden-İş, and Doğukan Akan, a trainee lawyer, were briefly detained earlier this month and are under criminal investigation for social media posts protesting Işık’s detention. They face potential charges of publicly disseminating misleading information.

The public prosecutor accuses Işık of “insulting” and “resisting the orders of a public official,” for which the faces up to seven years’ imprisonment. Her case exemplifies the official hostility toward peaceful environmental activism, in breach of Türkiye’s human rights obligations and incompatible with its duties as a COP31 co-host.

Türkiye’s detention of Işık for protesting coal mining, and the others for social media posts that fall squarely within the bounds of free speech, raises serious questions about the likelihood of it respecting those rights during COP31. How Türkiye treats its environmental defenders at home will determine whether it can meaningfully fulfill its duties as COP31 co-host. As a co-host, Türkiye should ensure that civil society and environmental defenders can meaningfully participate in the meeting alongside government officials, experts, journalists, and business representatives.

Turkish authorities should protect environmental defenders’ rights and stop criminalizing their right to peaceful protest and freedom of expression. Releasing Işık from detention at her first trial hearing next week and dropping charges against her and the other two would be a good start.