6.  The applicants were born in 1974 and 1977 respectively and live in Kielce. 7.  The first applicant (Ms D. Welke), had a school friend, Ms M.B., who was resident in the Netherlands. 8.  In January 2003 the Central Investigation Bureau (“CIB”; Centralne Biuro Śledcze) of the Police was informed by the German authorities about a parcel containing cocaine, which had been dispatched in Brazil and addressed to Ms E.B. in Kielce, Poland. On 3 February 2003 the Chief Police Commissioner (Komendant Główny Policji) authorised the covert surveillance of the parcel on the basis of section 19b § 1 of the Police Act. On 4 February 2003 the parcel was intercepted by officers of the CIB. They opened the parcel and found that it contained, in particular, fourteen plastic bags containing a white powder substance hidden by twos in seven cases. The police experts tested the substance and established that it was cocaine. The officers replaced the drugs with a similar-looking substance. 9.  On 5 February 2003 the Chief Police Commissioner ordered the covert operation (kontrola operacyjna w postaci podsłuchu pomieszczeń). It appears that the police placed a secret recording device in the parcel. 10.  On 6 February 2003 the parcel was delivered to Ms E.B. She was a friend of Ms M.B.’s late mother. On the same day Ms E.B. informed the first applicant that she had received a parcel from Brazil addressed to M.B. The first applicant telephoned her friend who confirmed that she was expecting a parcel and asked the first applicant if she could keep it for her. The first applicant agreed. 11.  On the same day the first applicant went to collect the parcel. She and Ms E.B. partly opened it and found tee-shirts and cardboard cases containing chain necklaces. They did not find anything else in the parcel. 12.  Subsequently Ms Welke took the parcel home, where she met her boyfriend Mr Białek (the second applicant). The applicants opened the parcel and examined its contents. Later on, they both left the flat to call Ms M.B. from a phone box. The first applicant put all contents of the parcel in a plastic bag together with parts of the original parcel indicating the addresses of the sender and the recipient. Then the first applicant hid the plastic bag in her room. 13.  On 6 February 2003 at around 8 p.m. the police arrested the applicants as they were leaving the flat. The officers then searched the flat. The first applicant, at the request of the officers, surrendered the plastic bag with all its contents. Examination of the contents revealed that in each of the seven cases containing chain necklaces were hidden two transparent plastic bags containing a white powder substance. The applicants were charged with drug-trafficking offences. 14.  On 8 February 2003 the Kielce Regional Prosecutor from the Organised Crime Department opened a criminal investigation into the alleged transfer of cocaine from Brazil to Poland. He relied on classified material provided by the Chief Police Commissioner and the information gathered by the CIB officers. 15.  On 8 February 2003 the Kielce District Court remanded the applicants in custody on reasonable suspicion that they had committed the drug-trafficking offences. It had regard to the evidence obtained so far in the case, in particular the witnesses’ statements, the classified evidence, the expert reports and the results of the search. The court noted that the applicants’ statements contradicted the other evidence in the case. On 23 June 2003 the Kielce Regional Court decided to end the applicants’ detention and to release them on bail. The bail was paid on the following day and the applicants were released. The court imposed non-custodial preventive measures on them. 16.  A significant part of the evidence gathered in the case was classified as confidential (poufne). On 9 April 2003 both applicants consulted the classified evidence and other evidence. They did not lodge any motions in respect of the evidence and did not make any comments on the investigation. 17.  On 18 April 2003 the prosecution filed a bill of indictment against the applicants with the Kielce Regional Court. They were charged with trafficking in 971 grams of cocaine. The prosecutor established the facts of the case on the basis of classified evidence, expert reports in chemistry and dactyloscopy, the results of the search of the flat and statements made by Ms E.B. and her friend Ms I.B., and partly on the basis of statements made by the applicants. 18.  Part of the case file and the written reasons for the bill were classified as it contained information covered by professional secrecy (tajemnica służbowa). The prosecutor asked the court for the defendants and their counsel to be allowed to consult the reasons for the bill of indictment, in accordance with the rules laid down in the Protection of Classified Information Act. Furthermore, invoking Article 360 § 1 (3) of the Code of Criminal Procedure (“CCP”), the prosecutor requested that the entire hearing be conducted in camera on account of the important State interests involved. 19.  The first applicant had two defence lawyers and the second applicant had one. On 12 and 26 May 2003 respectively the applicants and their counsel consulted the bill of indictment in the secret registry of the Kielce Regional Court. 20.  On 27 May 2003 the President of the 3rd Criminal Division of the Regional Court authorised the applicants, their counsel and the prosecutor to consult the record of the opening of the parcel, the transcript of the secret recordings and photographic evidence. On 28 May 2003 counsel for the first and second applicants consulted those materials in the secret registry. They were informed that they would be criminally liable in the event of their failure to respect the confidentiality of the information. 21.  The first hearing was set for 27 May 2003. At that hearing the court allowed the prosecutor’s request to conduct the trial in camera, having regard to the important State interests involved as provided for in Article 360 § 1 (3) of the CCP. The applicants’ counsel did not object to the prosecutor’s request. The court directed the persons present in the courtroom (the applicants, their counsel and three police officers) that they were under an obligation to keep confidential all information disclosed during the hearing. The applicants and their counsel could consult the case file in the secret registry of the court. 22.  The Kielce Regional Court held six hearings on the following dates: 27 May, 12 and 23 June, 22 July, 10 September and 8 October 2003. The Regional Court’s bench was composed of one professional judge and two lay judges. 23.  At the first hearing, held on 27 May 2003, the applicants pleaded not guilty. They refused to testify, but answered some questions from the court and their counsel. The trial court heard as witnesses Ms E.B., Ms I.B. and two other persons, friends of the applicants, who had been arrested with them. 24.  On 11 June 2003 the trial court received a copy of the decision of the Warsaw Regional Court of 12 February 2003 authorising the Chief Police Commissioner of 5 February 2003 to order the secret recordings. 25.  On 12 June 2003 the court provided the applicants with the transcript of secret recordings, on which they refused to comment. At the hearing held on 22 July 2003 the trial court heard the secret recordings made by the CIB. According to the applicants, the recordings were of very poor quality. The conversation between the first applicant and Ms E.B. was completely incomprehensible, and only vague extracts of the conversation between the applicants could be heard, interrupted by noises and rattling. 26.  At the hearings held on 10 September and 8 October 2003 the court heard CIB officers involved in the investigation, including those who had opened the parcel on 4 February 2003. The court authorised them to testify in respect of the facts covered by the duty of professional secrecy. 27.  At the hearing held on 10 September 2003 the first applicant requested the trial court to reverse its earlier decision to conduct the proceedings in camera. She submitted that as a consequence of that decision her defence rights had been limited because she had not been allowed to make notes from the file. Her counsel did not take a stand on the request, stating that it was the first applicant’s personal view. The prosecutor objected to the request, claiming that the grounds for the decision to exclude the public remained relevant. He also argued that the first applicant’s defence rights were duly respected as she could personally consult the classified part of the case file. The Regional Court dismissed the request to reverse the earlier decision to conduct the proceedings in camera as the grounds originally invoked for that decision remained fully valid. 28.  On 15 October 2003 the Kielce Regional Court gave judgment. It found the applicants guilty of having participated in the transit of cocaine through Poland in concert with other persons, and sentenced them to one year and six months’ imprisonment and a fine of PLN 1,500. It further ordered them to make a payment of 500 PLN to a local association fighting drug addiction and to reimburse the State’s costs incurred in the proceedings. The written reasons for the judgment were classified as confidential and deposited in the secret registry of the court. The applicants’ counsel were informed accordingly and notified of their right to consult the written reasons. They filed an appeal without consulting the written reasons for the judgment. 29.  When establishing the facts, the Regional Court excluded the evidence obtained by means of the secret recordings ordered by the Chief Police Commissioner on 5 February 2003. The Regional Court observed that the Police Commissioner’s order had not been endorsed by a court within five days as required by section 19 § 3 of the Police Act. Accordingly, the evidence obtained on the basis of that order was unlawful and could not be used in the criminal proceedings against the applicants. On the other hand, the Regional Court confirmed that the secret surveillance of the parcel and the replacement of the cocaine with an unspecified powder substance had been effected in accordance with the Police Act and the relevant Ordinance of the Minister of the Interior. 30.  On the basis of the available evidence, in particular, various statements made by the applicants during the investigation and during the trial, the Regional Court found that at the time when the parcel had been at their disposal the applicants had known that it contained drugs. The court found that the applicants had acted intentionally with a view to transferring the drugs through Poland to the Netherlands. Thus, their guilt had been sufficiently established. 31.  In their appeal, the applicants alleged breaches of several provisions of criminal procedure committed by the prosecution and the court, arbitrary assessment of evidence and disregard for the in dubio pro reo principle. They argued that the excluded evidence should have been omitted as the “fruit of the poisonous tree”, whereas the court had actually based the conviction on that evidence. Further, they submitted that the applicants’ right to defend themselves had been impaired because access to the classified evidence had been very difficult, and neither the applicants nor their lawyers had been allowed to make copies or notes of the written reasons for the judgment. 32.  On 5 February 2004 the Kraków Court of Appeal held a hearing at which the prosecutor requested the court to conduct the proceedings in camera. The applicants’ counsel left the issue to the court’s discretion. The Court of Appeal decided pursuant to Article 360 § 1 (3) of the CCP to allow the prosecutor’s request since the examination of the appeal would not be possible without consideration of the classified evidence. The Court of Appeal further decided to supplement the evidentiary material. It noted that the trial court had not determined the exact circumstances of the removal of the cocaine from the parcel and its replacement by a similar substance and decided, to this end, to hear four police officers who had been involved in the covert interception of the parcel. 33.  On 10 March 2004 the Kraków Court of Appeal held a hearing in camera. It heard evidence from three police officers and established that the cocaine had been removed from the parcel and replaced with a similar substance by the police. 34.  The prosecutor requested the Court of Appeal to hear the secret recordings and argued that the Regional Court had erred in excluding that evidence. The Court of Appeal rejected that request, noting that it could not examine the relevant decision of the Regional Court since the first-instance judgment had not been appealed against by the prosecutor (reformatio in peius). 35.  On the same date, after deliberations, the Court of Appeal amended the judgment of the Regional Court by changing the legal classification of the offence to one of “attempted” transit of drugs (usiłowanie nieudolne) as the police had secretly removed the drug from the parcel and replaced it with a similar substance. It accordingly reduced the applicants’ sentence to one year’s imprisonment. The judge rapporteur presented orally the main reasons for the judgment. The written reasons for the judgment were classified as confidential and could only be consulted in the secret registry of the court. 36.  The Court of Appeal confirmed that the applicants had taken part in the transit of cocaine through Poland. The first applicant had collected the parcel from the addressee and kept it in order to hand it over to a person indicated by Ms M.B.. She had also informed Ms M.B. of the collection of the parcel. The second applicant had assisted the first applicant in the process. 37.  The Court of Appeal held, inter alia, as follows:
“The applicants’ counsel are wrong to plead that the accused had no intention to take part in the transit of the drugs through Poland. This was sufficiently established by the [admitted] evidence, and in particular by the statements of the accused themselves. (...)
The applicants’ counsel are wrong to claim that the accused’s right to defend themselves was restricted on account of the fact that part of the evidence was classified, or that the judgment was the result of the fact that the judges had retained in their mind the content of excluded evidence. Both those situations are a simple consequence of the application of the relevant regulations, namely the regulation regarding classified information and the [regulation on] judicial review of the legality of evidence. ... 3.  The assertion that there was no equality of arms because part of the evidence was classified is incorrect. Such evidence was not withheld from the counsel, as they were able to consult it in the same manner as the prosecutor, and the restrictions on disclosure of classified material were equally applicable to both parties. 4.  (...) The consultation of classified evidence meant accepting certain conditions, including the prohibition on taking notes on the contents of such evidence; nonetheless those restrictions were not of such a nature that they could be considered to limit the rights of the defence. Counsel could memorise the content of the evidence they consulted, then use it, while respecting the requirements of confidentiality, either when pleading at the closed hearings or with due diligence in their written submissions. (...) Those were then not limitations on the rights of the defence, but rather certain impediments in conducting the defence, in any case impediments of a minor degree. In the Court of Appeal’s view, those limitations were necessary since part of the evidence was classified. If they [those limitations] were not applied, the interests protected by the regulation on classified information would be affected. [Those limitations] are present in every case concerning classified information, and thus alleging shortcomings in this respect does not concern just this particular case but relates generally to the principle of the determination of criminal charges based on evidence covered by the regulation on classified information. That would then be a claim of unconstitutionality in respect of the determination of such cases due to the limitation by that regulation of the constitutionally protected rights of the defence (Article 42 § 2 of the Constitution), which is far-reaching, unjustified and – for the Court of Appeal – unconvincing. If those arguments (or rather groundless assertions) of the author of such allegations were to be shared, then the determination of cases involving classified material would be ruled out. (...).” 38.  The Court of Appeal rejected the applicants’ claim that the trial court had based the conviction on the excluded evidence. In this respect it noted, inter alia:
“The allegation that the Regional Court’s ruling was influenced by the content of the excluded evidence, i.e. the evidence obtained secretly by the police and the explanations of the accused related to that evidence, is incorrect. Firstly, it is not uncommon in criminal proceedings that some evidence is removed from the scope of evidentiary material constituting the basis for a ruling. (...) Ensuring that judges did not know the evidence that was excluded would mean extinguishing those procedural acts in which such evidence was examined, removing the records of such information from the files and restarting every trial before a different panel of the court. That would not be reasonable and it is not provided for by law. (...) In other words, the Court of Appeal examines whether the evidence the Regional Court took as the basis for its ruling was sufficient for it to give the ruling or whether there was insufficient evidentiary basis for it. The Court of Appeal considers that there was sufficient evidence to give the judgment, and thus the judgment [of the Regional Court] has adequate evidentiary basis (with one reservation in respect of the presence of the drug in the parcel). The allegation that the judges [of the Regional Court] were influenced by the content of excluded evidence had no significance for the content of the judgment.” 39.  The applicants lodged cassation appeals. The second applicant’s lawyer submitted, inter alia, that the Court of Appeal had not referred to the arguments raised in the appeals, that in its assessment of evidence the court had infringed the principles of impartiality, presumption of innocence and in dubio pro reo. They repeated their arguments, submitted to the Court of Appeal, that the unlawfully obtained evidence, although eventually excluded by the first-instance court, had been presented during the trial as admissible evidence, which must have unfairly prejudiced the outcome of the proceedings. The defence also argued that since the evidence obtained by means of the secret recordings had been excluded at first instance, there had been no reason to hold the appeal proceedings in private. 40.  On 20 October 2004 the Supreme Court, sitting in camera in a single judge formation, dismissed the applicants’ cassation appeals, finding both of them manifestly ill-founded.