5.  The applicants, Ms Natalya Borisovna Trapeznikova, Ms Yuliya Sergeyevna Trapeznikova and Ms Anastasiya Sergeyevna Antonova, are Russian nationals who were born in 1969, 1985 and 2004 respectively and live in Novosibirsk. The applicants are members of the family of Mr Sergei Antonov. 6.  On 1 June 2006 Mr Antonov started serving a three-year prison sentence in correctional colony no. IK-8 in the Novosibirsk Region. When examined by a doctor on 5 June 2006, he stated that following a cranio‑cerebral injury he had been under psychiatric supervision since 1996 and that he had been suffering from drug addiction since 2004. 7.  On 4 May 2006 Mr Antonov had swallowed several metal objects, including a spoon, and had cut himself on his stomach. On 5 May 2006 he had been taken to hospital and had been treated until 19 May 2006. 8.  On 20 July 2007 Mr Antonov was transferred to disciplinary cell no. 14 for smoking outside the designated area. On 22 July 2007 he complained of a headache and of feeling ill. At 7.10 p.m. Doctor M. examined Mr Antonov, noted that he had high blood pressure and gave him an injection. On the doctor’s recommendation, Mr Antonov was transferred to another cell in the disciplinary section, where he was detained alone. As requested by the doctor, he was provided with bed linen. Doctor M. examined Mr Antonov again at 9.25 p.m. and noted that his condition had improved. At 9.40 p.m. the cell where Mr Antonov was held was locked and the alarm system was turned on. The guards in charge of the disciplinary cells observed Mr Antonov at 1.06 a.m. on 23 July 2007 through a peephole in the cell door. He was lying on his bed. During the next round of visits at 1.30 a.m. the guards saw Mr Antonov, hanging. They reported this to the duty officer. After entering the cell, the officers discovered Mr Antonov hanging by a ligature fashioned out of a bed sheet. They cut the rope and put his body on the floor. Doctor M. examined Mr Antonov’s body and noted no injuries apart from the ligature mark on his neck. 9.  According to the death certificate, Mr Antonov died on 22 July 2007. 10.  According to an autopsy conducted on 24 July 2007, the cause of death was asphyxiation by hanging. In addition to the ligature mark on his neck, the forensic expert Ch. documented bruises on the deceased’s head behind the left ear, at the corner of his right eye, on the right cheek and on the right side of the lower jaw. The expert decided against conducting a histological examination given that he had no doubts about the cause of Mr Antonov’s death. 11.  On an unspecified date the acting head of the correctional colony conducted an internal inquiry. He established that despite Mr Antonov’s condition the administration of the correctional colony had not provided him with any psychiatric supervision or treatment. It had been obvious from Mr Antonov’s case file that he had had suicidal tendencies. 12.  On 28 July 2007 the deputy city prosecutor K. refused to institute a criminal investigation into Mr Antonov’s death. The investigator based his decision on the reports filed by Doctor M. and the officers who had discovered Mr Antonov’s body, the report on the inspection of the cell where Mr Antonov had been found and on his body, and on his medical file. He also questioned prisoners Bel., F. and Ber. who had been detained with the deceased in cell no. 14, where he had been held prior to his removal to a cell where he was found. They submitted that they had not had any conflicts with him. 13.  On 31 July 2007 the first applicant asked the regional prosecutor to institute a criminal investigation into Mr Antonov’s death. Referring to the numerous injuries on Mr Antonov’s body, she challenged the official version that he had committed suicide by hanging himself. 14.  On 22 August 2007 the city prosecutor P. quashed the decision of 28 July 2007 and ordered a further inquiry into the circumstances of Mr Antonov’s death. Referring to the first applicant’s complaint, he considered it necessary to determine the existence and origin of the injuries on Mr Antonov’s body. 15.  On 28 August 2007 deputy city prosecutor K. refused to open a criminal investigation into Mr Antonov’s death. The prosecutor again questioned F., Ber. and Bel., who had been detained with Mr Antonov in cell no. 14 on 22 July 2007. They submitted that it had been very stuffy in the cell and that at around 4 p.m. Mr Antonov had complained of a headache. He had been sitting at the table, had stood up and had then fallen down, hitting his head against the table. They had not noticed any injuries on Mr Antonov. The prosecutor concluded that Mr Antonov had committed suicide by hanging himself. 16.  On 13 September 2007 the first applicant appealed against the decision of 28 August 2007. 17.  On 23 September 2007 the deputy regional prosecutor A. quashed the decision of 28 August 2007 and ordered a further inquiry. He noted that it was necessary to obtain information concerning Mr Antonov’s health, to determine whether the medical assistance provided to him had been sufficient and prompt and to establish whether it had been known that Mr Antonov had intended to commit suicide. The prosecutor also ordered the noose used by Mr Antonov to be found and for it to be examined. Lastly, the prosecutor noted that the inquiry had failed to take into account the injuries on Mr Antonov’s head and that it was necessary to determine their origin and whether they had had any connection with his death. 18.  On 18 October 2007 investigator Fom. refused to open a criminal investigation into Mr Antonov’s death, repeating verbatim the findings of the previous inquiry. 19.  On 29 October 2008 a supervising prosecutor quashed the decision of 18 October 2007 as premature and unsubstantiated. 20.  On 8 November 2007 investigator Fom. again refused to open a criminal investigation into Mr Antonov’s death. In addition to the earlier findings the investigator examined Mr Antonov’s medical file. He again questioned Doctor M. about the state of Mr Antonov’s health on 22 July 2007. The doctor explained that following the treatment he had been given Mr Antonov had been in a satisfactory condition and that it had been possible to leave him alone in a cell. The investigator also questioned the forensic medical expert Ch., who had conducted the autopsy. The expert considered that the injuries on Mr Antonov’s head could have been due to convulsions which had caused an impact with blunt, solid objects. 21.  On 12 November 2007 the supervising prosecutor dismissed the first applicant’s complaint against the decision of 8 November 2007. 22.  On 18 January 2008 the first deputy head of the regional investigative committee quashed the decision of 8 November 2007 and ordered a further inquiry, noting that the prosecutor’s instructions of 23 September 2007 had not been followed. 23.  On 1 February 2008 investigator Am. refused to institute criminal proceedings. Relying on the materials of the previous inquiries, the investigator confirmed the earlier finding that Mr Antonov had committed suicide. The investigator could not establish the cause and time of the injuries on Mr Antonov’s body, but he noted that they were not related to his death. 24.  On 16 September 2008 the head of the regional investigative committee quashed the decision of 1 February 2008. 25.  On 30 September 2008 investigator V. again refused to open a criminal investigation, relying on the earlier findings. On 13 October 2008 that decision was quashed on the grounds of the incompleteness of the inquiry. 26.  The investigating authorities subsequently refused to open a criminal investigation into Mr Antonov’s death on 25 October 2008 and 2 January 2009. On 8 December 2008 and 12 January 2009 respectively the supervising prosecutor quashed those decisions and ordered a further inquiry into the matter, noting each time that the inquiry had been incomplete and the findings contradictory. In particular, on 8 December 2008, the regional prosecutor noted that the reports of 23 July 2007 and 23 October 2008 concerning the inspection of the cell where Mr Antonov had been found had given different and mutually contradictory descriptions of the layout of the cell. 27.  On an unspecified date a senior investigator, S., started another inquiry in response to the first applicant’s complaint. The investigator questioned the correctional colony officers who had been on duty on 22 July to 23 July 2007 and had seen or observed Mr Antonov on those days. She also saw Ozh., the prison psychiatrist, and a drug counsellor, Kot. Ozh. stated that he had never seen Mr Antonov or prescribed him any psychiatric supervision or treatment. After studying Mr Antonov’s medical file, the investigator established that he had a history of drug addiction, one instance of self-harming and had undergone treatment in a psychiatric institution prior to his incarceration. The investigator noted that the cell where Mr Antonov had been found dead had been mistakenly indicated in the inquiry case file as no. 38 and conducted an examination of cell no. 00. On 11 February 2009 the investigator talked to the forensic expert Ch., who submitted that his superior had advised him against making any written statements about the autopsy. If necessary, the investigator could question him as a witness within the framework of the criminal proceedings. On 13 February 2009 S. concluded that Mr Antonov had committed suicide and refused to open a criminal investigation into his death. She also considered that the injuries found on Mr Antonov’s head had resulted from convulsions which had caused his body to repeatedly strike against a metal grill. 28.  The senior investigator’s decision was subjected to judicial review at two levels of jurisdiction. On 11 March and 27 April 2009 the Dzerzhinskiy District Court of Novosibirsk and the Novosibirsk Regional Court respectively upheld the investigator’s findings on Mr Antonov’s death.