6.  The applicants, Mr Ömer Yaman (first applicant), Mr Mustafa Ürek (second applicant), and Mr Kerem Bilen (third applicant) were born in 1956, 1967 and 1977 respectively. 7.  On 20 June 1999 the applicants were arrested in the course of a military operation in Şırnak. They were subsequently interrogated by the gendarmes in the absence of a lawyer. In their statements, the applicants accepted the charges against them and gave a detailed account of their involvement in the PKK (the Workers’ Party of Kurdistan, an illegal organisation). 8.  On 23 June 1999 the applicants were brought before the Diyarbakır Public Prosecutor and subsequently before the investigating judge. The first and second applicants were provided with an interpreter during their interrogation. Before the public prosecutor and the judge, the applicants denied the charges against them. They further stated that they had signed their gendarmerie statements without reading them. Following the questioning, the investigating judge remanded the applicants in custody. 9.  On 2 July 1999 the Public Prosecutor at the Diyarbakır State Security Court filed an indictment with that court and accused the applicants of carrying out activities for the purpose of bringing about the secession of part of the national territory, under Article 125 of the Criminal Code. 10.  The proceedings resumed before the Diyarbakır State Security Court and the first and second applicants were authorised to have the assistance of an interpreter. In their defence submissions before the trial court, the applicants retracted the statements they had allegedly made during the preliminary investigation stage. They submitted that the gendarmes had made them sign their statements without reading them. 11.  On 7 May 2002 the Diyarbakır State Security Court found the applicants guilty as charged and convicted them under Article 125 of the former Criminal Code with carrying out activities with the aim of bringing about the secession of part of the national territory. It further sentenced the applicants to life imprisonment. In convicting them, the court had regard to the applicants’ statements taken by the gendarmes. 12.  On 25 March 2003 the Court of Cassation quashed the judgment of the first-instance court on the ground that during the trial certain witness statements, which had been taken on commission before other courts, had not been read out to the applicants for comment during the trial. The case was accordingly remitted to the Diyarbakır State Security Court. 13.  In the meantime, State Security Courts were abolished by Law no. 5190 of 16 June 2004, and therefore, the case against the applicants was transferred to the Diyarbakır Assize Court. 14.  On 7 March 2005 the Diyarbakır Assize Court complied with the decision of the Court of Cassation and witness statements that had been taken on commission were read out to the applicants for their comments. At the end of the trial, the Diyarbakır Assize Court found the applicants guilty as charged and sentenced them to life imprisonment. 15.  On 17 June 2005 the Principal Public Prosecutor at the Court of Cassation decided that the case file should be remitted to the Diyarbakır Assize Court for examination of whether the new Criminal Code which had entered into force on 1 June 2005 (Law no. 5297) provided more favourable provisions for the applicants. The case was thus once again examined by the Diyarbakır Assize Court in view of the recent legislative changes. 16.  On 25 October 2005 the Diyarbakır Assize Court once again convicted the applicants under Article 125 of the former Criminal Court, finding that this provision was more favourable to them than the corresponding provision of the new criminal code. 17.  On 30 May 2006 the Court of Cassation quashed the judgment on procedural grounds, holding in particular that certain documents which had been relied on by the first-instance court in its judgment were not of an official nature. 18.  On 24 April 2007 the Diyarbakır Assize Court, after obtaining official copies of all the documents in the case file, convicted the applicants under Article 125 of the former Criminal Code and sentenced them to life imprisonment. 19.  On 11 December 2007 the Court of Cassation upheld the judgment of the first-instance court.