5.  The applicant was born in 1987 and lives in Moscow. 6.  The background facts relating to the planning, conduct and dispersal of the public event at Bolotnaya Square are set out in more detail in Frumkin v. Russia (no. 74568/12, §§ 7-65, 5 January 2016), and Yaroslav Belousov v. Russia (nos. 2653/13 and 60980/14, §§ 7-33, 4 October 2016). The parties’ submissions on the circumstances directly relevant to the present case are set out below. 7.  On 6 May 2012 a public demonstration entitled the “March of Millions” was held in central Moscow to protest against allegedly rigged presidential elections. The event had been approved by the city authorities in the form of a march followed by a meeting at Bolotnaya Square, which was supposed to end at 7.30 p.m. The march was peaceful and held without any disruptions, but when the marchers arrived at Bolotnaya Square it turned out that barriers installed by the police had narrowed the entrance to the meeting venue, allegedly restricting the space allocated for the meeting. To control the crowd the police cordon forced the protestors to remain within the barriers. There were numerous clashes between the police and protesters. At 5.30 p.m. the police ordered that the meeting finish early and began to disperse the participants. It took them about two hours to clear the protestors from the square. 8.  On the same day the Moscow city department of the Investigative Committee of the Russian Federation opened criminal proceedings to investigate suspected acts of mass disorder and violence against the police (Articles 212 § 2 and 318 § 1 of the Criminal Code). On 18 May 2012 the file was transferred to the headquarters of the Investigative Committee for further investigation. On 28 May 2012 an investigation was also launched into the criminal offence of organising acts of mass disorder (Article 212 § 1 of the Criminal Code). The two criminal cases were joined on the same day. 9.  The applicant took part in the demonstration of 6 May 2012 at Bolotnaya Square. He was arrested on the date indicated below and charged with participation in mass disorder. The applicant was detained and tried on those charges but subsequently exempted from liability under the Amnesty Act. 10.  The applicant is a political activist and a member of an opposition movement called Levyy Front. On 6 May 2012 he arrived at Bolotnaya Square to participate in the demonstration and, according to him, did not take part in any disorder or clashes with the police. After the events in question the applicant continued to live at his usual address and pursue his customary activities, including taking part in authorised public events. 11.  On 10 June 2012 the applicant was detained on suspicion of participation in acts of mass disorder and committing violent acts against the police on 6 May 2012. On 11 June 2012 the Basmannyy District Court of Moscow held a hearing on the investigating authorities’ request to detain the applicant pending the completion of the criminal investigation. In view of the need to provide additional evidence in support of the request, the court adjourned the hearing and authorised the applicant’s detention for seventy‑two hours. 12.  On 14 June 2012 the Basmannyy District Court ordered the applicant’s pre-trial detention until 10 August 2012. It referred to the gravity of the charges and stated that the applicant’s state of health did not preclude his being detained. The District Court concluded that the applicant, faced with the risk of a prison term, might obstruct the proper administration of justice or abscond. 13.  On 19 June 2012 charges were brought against the applicant under Article 212 § 2 (participation in mass disorder accompanied by violence) of the Criminal Code. He was accused, in particular, of having thrown an unidentified solid object towards the police. 14.  On 11 July 2012 the Moscow City Court upheld the detention order of 14 June 2012. 15.  On 8 August 2012 the Basmannyy District Court examined a request for an extension of the applicant’s pre-trial detention. The applicant requested to be released, arguing that all the necessary investigative acts had already been carried out. He presented personal guarantees from two State Duma deputies in support of an undertaking by him to appear before the investigating authorities and the courts for examination of his case. The applicant also requested his release on health grounds and submitted a medical document from 2004 which showed that he had a number of eye conditions. 16.  On the same day the District Court granted an extension of the applicant’s pre-trial detention until 6 November 2012. It relied on the reasons for and the nature of the crime which had been committed, which gave sufficient grounds to presume that the applicant might reoffend, influence and threaten witnesses and other participants of the criminal proceedings, destroy evidence or otherwise obstruct the proper administration of justice. In addition, the applicant had negative reports related to his place of residence. In particular, he had no permanent employment or family and had been repeatedly brought to administrative responsibility. His state of health was satisfactory and did not warrant his release. Lastly, the court held that in view of the above circumstances the custodial measure could not be replaced by a more lenient preventive measure. 17.  On 12 September 2012 the Moscow City Court upheld the extension order of 8 August 2012. 18.  On 29 October 2012 the Basmannyy District Court examined a new request for an extension of the applicant’s pre-trial detention. The applicant argued that his detention was detrimental to his health, in particular his eyesight. He referred again to the personal guarantees of two State Duma deputies in support of his request for a milder preventive measure. On the same day the court extended the applicant’s detention until 6 March 2013. The court referred to the gravity of the charges and the nature of the offence imputed to the applicant, along with information about his personality, namely that he had no permanent employment or regular source of income and had negative reports from his place of residence. 19.  On 7 November 2012 the charges against the applicant were updated. The classification of the offence remained unchanged. According to the new indictment, between 4 p.m. and 8 p.m. on 6 May 2012 at Bolotnaya Square unidentified persons had called those present to move outside the agreed meeting area and to disobey lawful police orders, leading to mass disorder accompanied by violence against public officials. Between 5 p.m. and 10 p.m. that day the applicant had taken part in acts of mass disorder, in particular, he had repeatedly shouted anti-government slogans. During that period of time the participants of the mass disorder threw pieces of tarmac, stones, sticks and other objects at the police, which hit them on various parts of their body. The applicant, no later than at 8 p.m., found a flagpole and threw it at an unidentified police officer, hitting him in the chest. 20.  On 26 November 2012 the Moscow City Court upheld the extension order of 29 October 2012. 21.  On 1 March 2013 the Basmannyy District Court granted a new extension of the applicant’s detention, until 10 June 2013. It stressed the complexity of the case, reiterated the grounds given in the previous orders and noted that the circumstances that had justified the detention order had not changed. The applicant asked to be released on bail and presented personal guarantees from a well‑known writer and two directors of prominent NGOs, but the court considered that a milder preventive measure could not be applied. The Moscow City Court upheld the extension order on 3 April 2013. 22.  On 23 April 2013 the Moscow City Court examined a fresh request to extend the applicant’s detention and set a new term of 6 July 2013 on the same grounds as previously. 23.  On 16 May 2013 the Moscow City Court examined an appeal by the applicant against its decision of 23 April 2013 and reversed it on the grounds that the prosecutor’s office would have enough time to bring an indictment by 10 June 2013, adding that after that date the trial court could consider a new extension of the applicant’s pre-trial detention. 24.  On 24 May 2013 the applicant’s criminal case was transferred to the Zamoskvoretskiy District Court of Moscow for the determination of criminal charges. 25.  On 6 June 2013 that court granted another extension of the applicant’s detention, until 24 November 2013. The decision concerned eleven defendants. Along with the gravity of the charges, the court based its decision on the findings that “the reasons which had initially warranted the detention have not changed” and that “no other measures of restraint would secure the aims and goals of the judicial proceedings”. The court also pointed out that the applicant’s state of health was not incompatible with his being kept in custody. The Moscow City Court upheld the extension order on 2 July 2013. 26.  On 18 June 2013 the Zamoskvoretskiy District Court began the trial in a criminal case against ten participants in the demonstration at Bolotnaya Square, who were charged with participation in acts of mass disorder and committing acts of violence against police officers. 27.  The applicant made an application for release during a court hearing on 6 August 2013 but it was dismissed by the Zamoskvoretskiy District Court on the same day. 28.  On 11 September 2013 the Ombudsman of the Russian Federation submitted a complaint to the Presidium of the Moscow City Court about the extension of the applicant’s pre-trial detention and requested an alternative preventive measure for him. 29.  On 1 November 2013 the Moscow City Court refused the Ombudsman’s request. 30.  On 19 November 2013 the Zamoskvoretskiy District Court granted another extension of detention in respect of ten defendants, including the applicant. It ordered their detention until 24 February 2014 on the grounds of the gravity of the charges and the nature of the offences imputable to them. On 17 December 2013 the Moscow City Court upheld that extension order. 31.  On 18 December 2013 the State Duma passed the Amnesty Act which applied, inter alia, to pending criminal proceedings against people suspected and accused of criminal offences under Article 212 §§ 2 and 3 of the Criminal Code. 32.  On 19 December 2013 the applicant requested the termination of the criminal proceedings against him by operation of the Amnesty Act. On the same day the Zamoskvoretskiy District Court granted the request and released him from detention. 33.  The applicant has moderate myopia, complex myopic astigmatism and a congenital coloboma of the choroid. 34.  From 23 June 2012 to 17 September 2012 and from 4 November 2012 to 29 June 2013 the applicant was held in remand prison IZ-77/5 in Moscow. Upon his arrival there he was given a medical check which did not reveal any health issues. 35.  In IZ-77/5 the applicant was detained in cells 320 (until 29 June 2012), 406 (until 17 September 2012, then from 4 to 30 November 2012), 509 (until 10 December 2012), 506 (until 19 June 2013), and 507 (until 29 June 2013). 36.  The cells had the following characteristics: 37.  The parties agreed that on most days the number of inmates in the cell did not exceeded the design capacity. They also agreed that the size of the cells and the number of detainees had allowed the applicant four square metres of personal space and that the applicant had had an individual sleeping place in every cell. 38.  The parties provided the following accounts of the conditions in the cells. According to the applicant, the cells were inadequately lit and ventilated, were excessively hot in the summer and cold in the winter, they all had a lavatory pan which was separated from the living space by a plastic partition to chin level, which did not provide enough privacy. The applicant alleged that he had been constantly exposed to cigarette smoke and that although the window in the cell could be opened, it overlooked a courtyard used for incinerating rubbish and had let in fumes. There was therefore a constant lack of fresh air in the cell, which the ventilation system could not compensate for. Outdoor exercise was limited to one hour per day. The applicant also stated that the window was too high to give sufficient light for reading or working on documents. Finally, he alleged that the purchase of an electric kettle was a condition for access to drinking water. 39.  According to the Government, the cells were equipped with ventilation; the state of the sanitary facilities had been satisfactory; the cells had been cleaned and bedding changed once a week; the applicant had been entitled to one hour of outdoor exercise per day; and the cells had been disinfected and subjected to pest control monthly. They provided measurement tables for the remand prison, which had been created in August 2013. They showed that the level of light in the cells in which the applicant had been detained had ranged between 152 and 264 lux, the standard being 150 lux. The temperature in the cells had measured between 26oC and 28oC and humidity between 41% and 47%, while the permissible level was up to 28oC and 65% respectively. The Government also noted that detainees had access to a gym upon a written request. 40.  On 11 July 2012 the applicant’s lawyer requested that the head of the remand prison order a medical examination for the applicant. He alleged that there had been a rapid deterioration of his eyesight. 41.  On 16 July 2012 the public commission for the monitoring of detention facilities visited IZ-77/5, and the applicant complained to them about excessive heat in his cell and a deterioration of his eyesight. 42.  On 30 July 2012 the applicant requested that the head of the remand prison organise a medical examination owing to his worsening eyesight. 43.  On 27 August 2012 the applicant was taken for an outpatient consultation with an ophthalmologist. He was diagnosed with severe myopia, amblyopia, esotropia, and a congenital coloboma of the iris. The doctor noted that the applicant had last been examined in October 2004 and recommended that he have a special examination to determine his disability status (медико-социальная экспертиза). 44.  On 8 November 2012 the chief of IZ-77/5 requested another ophthalmologic consultation, repeating the applicant’s complaints about the deterioration of his eyesight. 45.  On 23 November 2012 the applicant was taken for another outpatient consultation with an ophthalmologist, who concluded that there were no negative developments in his state of health. The doctor also recommended that he have eye tests once a year. 46.  On 13 December 2012 the applicant underwent the special examination for recognition of the status of being disabled, which he was refused. 47.  On 29 March and 19 April 2013 the public commission for the monitoring of detention facilities visited IZ-77/5, and the applicant complained to them about the poor quality of his mattress and the deterioration of his eyesight. 48.  On 17 September 2012 the applicant was transferred to remand prison IZ-77/1 in Moscow (Матросская тишина), which had a medical wing. The applicant remained there until 4 November 2012 and underwent a series of medical examinations, including blood tests, an echography, a chest photofluorography and an electrocardiogram. 49.  According to the applicant, the prison cell measured 4 by 3.5 square metres and housed four inmates, including himself. The window measured 1.75 by 0.5 metres and was too high to give sufficient light for reading or working on documents. The artificial light was dim and flickering and was turned on even at night. There was no mechanical ventilation and the cell was damp, with broken window panes letting in the cold. A shower was allowed once a week and the toilet was only separated from the rest of the cell by a low wall. Outdoor exercise was limited to one hour per day and the purchase of an electric kettle was a condition for getting access to drinking water. 50.  According to the certificate issued by the prison governor on 13 November 2013, the applicant was held in cell 707 in IZ-77/1. That cell had measured 16 square metres and had housed four inmates, including the applicant. The cell had one window measuring 115 by 170 cm and the state of the glazing was inspected every day and fixed whenever necessary. The temperature in the cell had been maintained at 18oC. Artificial light was provided by a fluorescent lamp with two 40-watt tubes from 6 a.m. to 10 p.m. and by a 40-watt lamp during the night, in line with requirements. The windows had no shutters, only a metal grill with 20-mm metal bars; the size of the mesh was 100 by 200 mm. Inmates had to clean the cell each day with chlorine bleach and detergent provided by the facility. The applicant had been able to shower once a week for fifteen minutes. The cell had been disinfected and subjected to pest control measures regularly. 51.  On 16 October 2012 the applicant was examined by a commission of four doctors, including an ophthalmologist. They issued a report which, in so far as relevant, read as follows:
“... According to the [the applicant’s] medical documents, dated from 1997 to 2004, [he had been diagnosed with] medium myopia, complex myopic astigmatism, a congenital coloboma of the choroid, and a vascular congenital coloboma of the iris. Partial optic atrophy.
According to the results of the medical examination in [IZ-77/1] carried out on 5 October 2012 [he has] high myopia of the right eye. High-degree amblyopia of the left eye, esotropia. A congenital coloboma of the iris [and] of the choroid.
...
There have been no negative developments compared with the previous evaluation reports (medical examinations).” 52.  On 31 October 2012 the public commission for the monitoring of detention facilities visited IZ-77/1 to check the conditions of the applicant’s detention. Its report read as follows:
“[The applicant] is being held in a cell in the remand prison’s medical wing. There are two other detainees in the cell. The cell is one of the worst in the medical wing of [IZ-77/1]. It is cold, the radiator is lukewarm and the glass in the hinged window is broken. The cell has not been renovated for a long time. Dirty, scuffed walls. There is no refrigerator or television, the radio socket is broken. [The applicant] complains that he has not received any treatment in the hospital for three weeks. The medical wing of the remand prison has no ophthalmologist and he was taken for a consultation to the [city hospital] ... According to the chief physician of the medical wing ... [the applicant] had 10% sight in one eye and 20% sight in the other. But the prison doctors could not recommend his release ... because only totally blind detainees are eligible.
... [The applicant’s] detention is detrimental to his health, his eyesight is deteriorating as each day goes by: the light is always on in the cell, day and night. The light is dim; that is bad for his eyesight.
...
The members of the [commission] consider that [the applicant’s] detention ... is a way to pressure him into giving the evidence the investigation wants. [He] risks losing his remaining eyesight. It is evident that he has been placed in the worst cell, cold and damp, instead of being treated in the hospital. He has been deprived of the possibility to receive visits from his family and has found himself in an information vacuum, without any television, radio or press. No adequate treatment or medical care.” 53.  On 2 November 2012 the applicant was taken for an outpatient consultation with an ophthalmologist, who confirmed the previous diagnoses and identified no change in the applicant’s condition. 54.  The discharge summary (выписной эпикриз) issued on 4 November 2012 contained the results of the applicant’s medical examinations carried out in IZ-77/1. The head of the prison’s medical wing concluded that they did not reveal the presence of any of the serious conditions which were listed as being incompatible with custody and there were thus no obstacles to the applicant’s detention. 55.  On 30 June 2013 the applicant was placed in remand prison IZ-77/2 in Moscow (Бутырская тюрьма) where he was held until his release on 19 December 2013. 56.  In IZ-77/2 the applicant was detained in cells 52 (until 7 July 2013), 01-a (until 12 July 2013), 703 (until 2 September 2013), 332 (until 19 September 2013), and 327 (apparently until his release). 57.  The cells had the following characteristics: 58.  According to the applicant, the conditions in IZ-77/2 were poor, especially because of a lack of regular outdoor exercise and inadequate sanitary arrangements. In particular, the lavatory pan was only separated from the living space by a chest-high partition which did not provide sufficient privacy. In addition, the applicant did not take a shower after his transfer to IZ-77/2 until at least 30 July 2013, as he indicated in his letter. 59.  According to the Government, the conditions in the cells at IZ-77/2 were as follows: the toilet was separated by a solid partition from the rest of the cell, which provided the necessary privacy; the state of the sanitary facilities was satisfactory; the cells were disinfected and subjected to a pest control procedure once every three months or whenever necessary; the applicant had been entitled to one hour of outdoor exercise daily; the cell had been cleaned and the bedding changed weekly; the cells were equipped with forced ventilation and could be aired through a hinged window. Artificial light was provided from a 100-watt bulb by day and a 75-watt bulb by night. The glazing of the windows let in sufficient daylight. 60.  On 12 July 2013 the applicant was placed in the medical wing of IZ‑77/2 for an additional examination and adjustment of his treatment. He had been discharged on 18 July 2013 after refusing further treatment. 61.  According to a statement of 7 November 2013 issued by IZ-77/2, the applicant’s state of health had been satisfactory and doctors had recommended that he have regular consultations with an ophthalmologist. 62.  The applicant’s description of the conditions of detention during his transfer from the remand prison to court and back was identical to that in the case of Yaroslav Belousov (cited above, §§ 69-73). 63.  On 6 June 2013 court proceedings began in hearing room no. 338 and in the end of July moved to hearing room no. 635 at the Moscow City Court. The defendants, including the applicant, were held in glass cabins in both hearing rooms. From mid-September 2013 to the end of 2013 the hearings continued at the Nikulinskiy District Court of Moscow in hearing room no. 303, which was equipped with metal cages. 64.  For a detailed description of the conditions in those hearing rooms see Yaroslav Belousov (ibid., §§ 74-77).