5.  The applicant was born in 1966 and lives in Diyarbakır.
6.  At the time of the events he was a lawyer practising in that city.
7.  On 18 April 2000 the applicant was questioned by the public prosecutor at the Diyarbakır State Security Court, on suspicion of membership of an illegal organisation, namely Hizbullah. The contents of a computer disk holding detailed information on the applicant’s background, which had been obtained by the security forces in a house belonging to Hizbullah, and police statements of four people, all of whom were accused of being members of the same illegal organisation, were read out to him during the questioning. The applicant denied having any affiliation with the illegal organisation and contested the accuracy of the evidence presented to him. He maintained that he had assisted certain members of Hizbullah as a lawyer and that he always acted within the limits of his profession, without directing those people’s submissions as alleged. He further maintained that certain information in the illegal organisation’s background report, such as the ages of his siblings, was wrong and that this in itself proved that he had not provided the information. He did not benefit from the assistance of a lawyer during questioning.
8.  On the same day the applicant gave statements before the investigating judge of the Diyarbakır State Security Court, this time together with his business partner, who was accused of being a member of the same illegal organisation. He reiterated his submissions given to the public prosecutor and added that the fact that he had provided legal assistance to some members of the illegal organisation might have been perceived as a demonstration of support by certain people. The investigating judge refused the public prosecutor’s request for the applicant’s detention and decided that he should be released pending trial.
9.  The following day, on 19 April 2000, the public prosecutor objected to the applicant’s release. The applicant was subsequently arrested on the basis of a warrant issued by the Diyarbakır State Security Court.
10.  On 20 April 2000 the applicant was taken before the investigating judge, who decided that he should be detained on remand.
11.  On the same day the public prosecutor filed a bill of indictment with the Diyarbakır State Security Court, accusing the applicant of membership of an illegal organisation. He relied on the police statements of the four witnesses as well as the background information obtained from the computer disk.
12.  On an unspecified date the applicant’s lawyers lodged a petition with the trial court. They argued that there was no evidence against the applicant in that all of the witnesses relied on by the prosecution had denied their statements later on. They further stated that the background information obtained from the computer disk was not reliable.
13.  At the hearing on 30 May 2000 the applicant’s lawyers once again challenged the use of the background information obtained from the computer disk, arguing that it was unreliable in that the disk had been de-encrypted and the information extracted in their absence. During the same hearing, the court noted that the four witnesses, who had mentioned the applicant in their police statements, had denied those submissions during the subsequent stages of the proceedings against them. The court held that the applicant should be released pending trial.
14.  On 3 September 2001, following statements made by a certain M.S.B., the public prosecutor drew up another bill of indictment against the applicant, once again accusing him of membership of an illegal organisation. The allegations put forward by this latter indictment were joined with the case which was already pending before the State Security Court.
15.  At the hearing on 4 December 2001, during which the applicant was not present, M.S.B.’s police statements were read out. On 30 April 2002 the court noted that M.S.B. had denied those statements at a later point.
16.  On an unspecified date the public prosecutor submitted his written observations to the court. He argued that the applicant’s guilt was proven by various items of evidence, namely the background report prepared in respect of him, which contained detailed personal information, as well as the background reports and police statements of several other members of Hizbullah. In that connection, he referred to the statements of a certain N.S., who had maintained before both the police and the public prosecutor that the applicant had been a recruiter for the illegal organisation, had given courses to new members and had been in charge of certain cells. The public prosecutor also noted that the applicant’s name had been mentioned in the background reports of several members, including a certain Ş.A.
17.  On 18 November 2003 the applicant’s lawyer applied for the expansion of the investigation and the cross-examination of the witnesses who had confirmed the applicant’s membership of Hizbullah. He mentioned, in particular, the names of N.S. and Ş.A., who had given statements against the applicant. The applicant’s lawyer further challenged the credibility of these two witnesses’ statements. In that connection, he argued that N.S. had not repeated his police statements against the applicant at a later point as alleged by the public prosecutor in his written opinion. The lawyer further noted that Ş.A. had claimed to have taken courses run by the applicant until the latter started his military service and asked the trial court to obtain information as regards the dates the applicant had served in the army in order to prove that those allegations were not credible.
18.  On 27 January 2004 the court refused the application for the expansion of the investigation, without stating anything as regards the cross-examination of witnesses.
19.  On 23 March 2004 the applicant applied to benefit from the Reintegration of Offenders into Society Act (Law no. 4959).
20.  During the course of the proceedings, the State Security Courts were abolished and the case was transferred to the Diyarbakır Assize Court.
21.  At the hearing on 21 February 2006 the Assize Court read out the police statements of Ş.A., in which he had claimed that the applicant had acted as a mentor within the illegal organisation and had given courses to other members, including him, which had ended when the applicant had started his military service. The trial court stated that although Ş.A. had reiterated his submissions in so far as they concerned himself before the public prosecutor and the investigating judge, he had not mentioned the applicant after his questioning by the police. The court nevertheless added the statements of N.S. and Ş.A. to the case file. The applicant’s lawyers maintained that they did not accept the statements against the applicant.
22.  On 18 April 2006 the Diyarbakır Assize Court found the applicant guilty as charged and sentenced him to six years and three months’ imprisonment. The court relied on certain information obtained from the computer disk, namely the background report on the applicant and reports concerning other members, as well as the statements of N.S. and Ş.A. It also refused the applicant’s application to benefit from Law no. 4959, finding that he had not disclosed any information about the structure of the illegal organisation.
23.  The applicant appealed against the judgment. He argued that the trial court had failed to hear evidence from N.S. and Ş.A. despite his requests to that effect and that he had been deprived of the possibility to put his questions to them.
24.  On 19 November 2007 the Court of Cassation upheld the judgment of the Diyarbakır Assize Court.