Demirtas’s detention has exceeded a reasonable period, the court said in a decision published in the Official Gazette on Friday. He should be compensated financially, it said.

The Kurdish politician has been in prison since November 2016 for his alleged links to terrorism and faces multiple life sentences if found guilty. Demirtas is among scores of Kurdish politicians who have been ousted from their positions or jailed on the same charges.

According to Cumhuriat newspaper, the court announced: "a reasonable period of time has passed since in detention, and during this time, no data has been reviewed regarding his detention. As a result, Article 19 of the Constitution has been violated. Furthermore, due to the extended duration of detention without the verdict, his personal freedom has been violated."

It was not immediately clear if the Constitutional Court’s decision would lead to Demirtas’s release as prosecutors have begun another probe against him. Turkish courts have released prominent political figures and human rights leaders in recent years only for them to be jailed again, sometimes within hours, on other charges.

The co-leader of the HDP, the second-biggest opposition party in Turkey’s parliament, Demirtas is known for his vocal criticism of President Recep Tayyip Erdogan and was a key contributor to the party’s successes, preventing Erdogan’s governing Justice and Development Party (AKP) from winning a legislative majority in elections in 2015. The polls were re-run later the same year. The HDP's election performance in 2018 also prevented an AKP majority.

Turkey accuses Demirtas and many other officials of the HDP of links to the outlawed Kurdistan Workers’ Party (HDP), accusations they all deny. The PKK has been fighting for Kurdish autonomy for four decades in a conflict that has cost almost 40,000 lives. The group is labeled as a terrorist organization by Turkey, the United States and the European Union.

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