Following the military coup attempt, Mehmet Altan was taken into custody on 1 September 2016 and was arrested on 22 September.
The trial proceedings were held by the İstanbul 26 Heavy Criminal Court and on 16 February, the first instance court found defendants Ahmet Altan, Mehmet Altan, Nazlı Ilıcak, Fevzi Yazıcı, Yakup Şimşek and Şükrü Tuğrul Özşengül guilty on overthrowing the constitutional order through violence and force and sentenced them to aggravated life imprisonment.
This decision was upheld by the the 2nd Penal Chamber of İstanbul Regional Court of Justice on 2 October 2018. The decision was appealed.
Meanwhile, Mehmet Altan lodged an application with the Constitutional Court and the court found that there were violations of right to freedom and liberty as well as freedom of expression and freedom of press. The court rendered its decision on 11 January 2018 however the first instance court did not impose the decision and release Mehmet Altan. Thus, Altan’s lawyer lodged an application with both the Constitutional Court and the European Court of Human Rights.
On 20 March 2018, ECtHR found that there were violations of right to freedom and liberty as well as freedom of expression and freedom of press.
Following these judgements, 2nd Penal Chamber of İstanbul Regional Court of Justice concluded that first instance courts are mandate to impose decisions of the Constitutional Court. Eventaully, Mehmet Altan was released on 27 June 2018 from Silivri Prison.
The 16th Penal Chamber of the Supreme Court of Appeals, reversed the decision of 2nd Penal Chamber of İstanbul Regional Court of Justice and concluded that due to lack of evidence, Mehmet Altan should be acquitted.
Upon this decision İstanbul 26. Heavy Criminal Court gave its verdict on November 4th and acquitted Mehmet Altan.
On January 9 2020, the Constitutional Court pronounced its decision pertaining Altan’s second application. TCC found violation of right to freedom and liberty and stressed that first instance court is not competent to scrutinize the lawfulness of TCC judgements and is obliged to decide in accordance. Court decided 30 thousand TL to be paid to Altan as compensation.