4.  The applicant was born in 1987 and is detained in Tiszalök. 5.  On 19 July 2012 at approximately 9 a.m. the applicant, who had been placed in pre-trial detention in Budapest Prison, was transported to the premises of the Budapest Main Police Department for questioning. He was accompanied by two guards and was handed over for questioning at around 9.20 a.m., when he showed no sign of injuries. 6.  The questioning started at approximately 9.55 a.m. and lasted until approximately 11.30 a.m. It was conducted by police officers A and B The applicant chose not to give a statement. 7.  On being released after the interrogation, the applicant was handed over to the guards of Budapest Prison who, in the presence of the police officer, asked him whether he had been ill-treated. The applicant declared that he had not been. 8.  After being transported back to Budapest Prison, the applicant underwent a medical examination before his readmission during which he claimed that he had been ill-treated by police officer A. Certain injuries were noted on the applicant. A report was drawn up on the incident and photos were taken of the injuries. 9.  Right after the medical examination the applicant was again transported to the Budapest Main Police Department for questioning, from where he was taken to the military hospital by the police officer conducting his interrogation and allegedly assaulting him. At the hospital he was examined in the presence of the police officer. The medical report noted bleeding on the lower lip, jaw sensitive to pressure, and bruises on the ribs, all likely to heal within eight days. 10.  According to the applicant’s submission, following his return to Budapest Prison, he was again subjected to a medical examination. 11.  The police report filed by A on 19 July 2012 stated that the applicant had not been ill-treated during questioning. None of the police officers had seen the applicant harming himself but A. had observed him biting his nails and lips. Also, according to the report, the applicant had been left alone for a few minutes at the police station without constant surveillance. 12.  On 20 July 2012 the applicant complained of a headache and dizziness and was again examined by medical staff at Budapest Prison. He asserted that he had been ill-treated during his interrogation. The medical report recorded the following injuries: swelling on the right cheek, head sensitive to pressure, bruising on the lower lip, and abrasions on the lower right ribs and on the left shoulder blade. 13.  Budapest Prison initiated criminal proceedings on charges of forced interrogation. Furthermore, the applicant’s statements given during the medical examination (see paragraph 8 above) were qualified as a criminal complaint by the investigation authorities. 14.  In the ensuing criminal investigation conducted by the Central Investigation Office the applicant gave a testimony on 14 November 2012, stating that during his questioning he had refused to make a statement and as a consequence had been punched by one of the police officers several times on his head, neck and back. He had fallen against a chair and when he had tried to get up, he had been slapped four or five times in the face. He had been shown the results of a DNA test, and when he refused to comment on it, had again been beaten by the police officer. The same police officer had also punched him in the mouth when he had failed to recognise a person shown to him in a photograph. He had been pushed against the door and when he again fell over, the police officer had kicked him on his left side. 15.  On 24 July 2013 one of the prisoner escort officers, C was questioned, and recalled that the applicant had complained of ill-treatment upon his return to the prison facility, which had surprised him since he had previously asked the applicant whether he had any complaints and had seen no injuries on the applicant’s body. He also stated that he had noted the injuries on the applicant’s face following the medical examination at Budapest Prison. He had asked the applicant why he had not complained of his ill-treatment earlier, to which the applicant had replied that he had been afraid of the police officers. According to C, as a general practice, detainees had been transferred in a special prisoner transport vehicle where they had not been constantly monitored and would have had the opportunity to inflict injuries on themselves. 16.  On 25 July 2013 D, the other prisoner escort officer who accompanied the applicant to his interrogation, was also heard as a witness. He did not remember either the applicant or the circumstances of his transfer. He had a vague recollection that since there had been some complaints from the applicant’s side once they had arrived back at the prison facility, they had had to transfer him back to the police department. He maintained that if they had seen any injury on the applicant’s face following interrogation, they would surely have inquired of him whether he had been ill-treated by the police officers. Therefore, in his estimation the applicant could not have shown any visible signs of injury when he was handed back from the interrogation. 17.  On 6 October 2013 E, the prison security officer who had taken photos of the applicant’s injuries during his readmission was questioned as a witness. He could not give any details of the incident. He could not remember whether he had escorted the applicant to the medical examination, but suggested that the applicant’s injuries must have occurred before he had been examined by the medical staff, which was why he had been called on to take photos. 18.  On 18 November 2013 F, the nurse on duty at Budapest Prison was questioned, but she did not remember the incident. She could only confirm that if she had seen the applicant’s injuries prior to his transfer, she would surely have inquired about their origin. Examining the photos of the applicant, she asserted that the bruises on the applicant’s face would have occurred immediately after an impact and that the applicant could have caused them himself. 19.  On 5 December 2013 G, the guard on duty at Budapest Prison, was questioned as a witness; he could not remember either the applicant or anything else concerning his complaint. He nonetheless maintained that if he had seen injuries on the applicant as presented to him on a photo, he would surely have inquired about their origin. 20.  On 2 January 2014 the Central Investigation Office also heard evidence from H and I, two prison escort officers from Budapest Prison who had been on duty on the day of the incident, and who were responsible for transferring detainees to the healthcare facilities. They did not remember the applicant and could not recall the circumstances of his medical examination or admission to the prison, since, as one of them explained, they were responsible for escorting thirty to forty prisoners a day. H stated that as a general practice detainees were under constant supervision while waiting for medical examinations, whereas I asserted that there were instances where detainees were left alone when placed in so‑called “healthcare waiting rooms”. Neither of the witnesses knew with certainty whether this had been the case for the applicant. 21.  On the same day, three members of the medical staff of Budapest Prison were also heard as witnesses. Two of them could not recall anything about the incident and did not remember the applicant, mostly because they were responsible for a large number of cases. Another member of the healthcare staff stated that she had a recollection of an incident, but was not sure whether it involved the applicant or another person. As a general rule, the witnesses explained that they would not admit a detainee into the prison if he showed signs of injuries. Examining the photos of the applicant, two of the medical staff stated that because of the bad quality of the photos, they weren’t even sure if they showed actual injuries or simply the shape of the applicant’s face, while the third asserted that the injury must have been fresh when the photo was taken. 22.  The prison doctor was also questioned the same day. She could not identify the applicant, did not remember whether she had met him, had no recollection of the incident and could only recount what she had previously stated in the medical report. However, she stated that if the applicant had been left alone, he could have inflicted the injuries on himself. 23.  The Central Investigation Office commissioned a forensic expert opinion. According to the expert assessment, the applicant’s account of the origins of his injuries was implausible, since if he had been ill-treated in the way described by him, his injuries would have been of a more serious nature. Furthermore, the location of the injuries had not corresponded to the applicant’s description of the incident either. The report stated that it was impossible to establish when the applicant’s injuries had occurred. Referring to the witness testimonies and the location of the injuries, it suggested that the applicant could have inflicted them on himself. 24.  The investigation was discontinued on 8 May 2014 on the grounds that the applicant’s allegations could not be substantiated beyond doubt in the absence of any witness testimony and taking into account the conclusions of the forensic expert opinion. According to the reasoning, the available evidence neither refuted nor proved the applicant’s allegations. The applicant complained, seeking the continuation of the investigations. The first-instance decision was upheld by the Chief Prosecutor’s Office on 15 July 2014. The decision called the applicant’s attention to the possibility of lodging of initiating substitute private prosecution proceedings.