4.  The applicant was born in 1944 and lives in Kremenchuk.
5.  On 11 August 2007 Inna Puzyr, the applicant’s daughter, was found stabbed to death in bushes by the roadside.
6.  On the same date the Poltava Regional Police instituted criminal proceedings into the suspected murder.
7.  On an unspecified date the applicant was called to testify as a witness in connection with the above investigation, and for this reason his subsequent request to join the proceedings as an aggrieved party was refused.
8.  On 18 August 2007 V.K., the applicant’s other daughter, joined the proceedings as an aggrieved party.
9.  On 25 August 2007 O.T., a resident of a village close to the place of where the applicant’s daughter was stabbed, was arrested on suspicion of having committed this crime. Having initially pleaded guilty, O.T. subsequently retracted his confession, denying any involvement with the crime and complaining that the police had subjected him to ill-treatment.
10.  On an unspecified date the criminal proceedings against O.T. were discontinued as no evidence had been collected to corroborate his confessional statements, which were inconsistent with other evidence on file.
11.  On 7 September 2007 V.K. complained to the Chief of the local police department that the investigation into the case had been ineffective. She also complained that she had not been able to participate in it in a meaningful way, as she had not been allowed to consult the case file and had been very poorly informed about the measures undertaken by the authorities with a view to identifying her sister’s murderer.
12.  On 12 September 2007 the Acting Chief of the Poltava Regional Police informed V.K. that he had detected no irregularities in the manner in which the investigation had been conducted and that ‒ according to the applicable law ‒ aggrieved parties were not entitled to consult case files until completion of the pre-trial investigation, that is to say, until the likely perpetrator has been identified and committed for trial.
13.  On 10 October 2007 the investigation was suspended as no leads had been identified.
14.  On 30 October 2007 the District Prosecutor’s Office quashed the decision to suspend the proceedings and ordered a further inquiry, noting that the investigation had been carried out in a perfunctory manner.
15.  On 20 November 2007 V.K. again complained to the Kremenchuk prosecutor’s office that the renewed investigation had, in her view, been perfunctory and ineffective. She submitted that she suspected R.P., her sister’s husband, of having murdered her and referred to numerous delays in carrying out the investigative activities, which ‒ in her view ‒ had resulted in the loss of important evidence.
16.  On 23 January 2008 the Chief of the Poltava Regional Department of the Interior acknowledged to V.K. that there had been many inadequacies in the investigation of her sister’s violent death and notified her that the chief and deputy chief of the investigative department had been reprimanded for poor planning of their department’s work and supervision of their subordinates. Investigator S.Y., who had worked on the case, had been replaced by V.N., who had extensive expertise in investigating homicide and other violent crimes.
17.  On 5 March 2008 R.P. was arrested and confessed to having killed the applicant’s daughter because she had refused to give him a divorce.
18.  On 6 March 2008 a reconstruction of the crime scene was organised, at which R.P. demonstrated how he had committed the murder.
19.  On an unspecified date R.P. retracted his confession, claiming it had been given under duress from the police.
20.  On 15 August 2008 the proceedings in respect of R.P. were discontinued in the light of irreconcilable discrepancies between his retracted confessional statements and other evidence on file. As there were no further leads pointing to a potential perpetrator, the proceedings were suspended.
21.  On 26 March 2009 the Poltava Regional Prosecutor’s Office notified V.K. ‒ in response to an enquiry from her concerning progress in the case ‒ that unspecified operative and inquisitorial activities had been underway, but that no leads had been uncovered.
22.  Following a new complaint by V.K. concerning the inadequacy of the investigation, on 20 May 2009 the Deputy Minister of Interior ordered a renewal of proceedings. Having consulted the case file, he noted that leads to at least two potential perpetrators had not been properly followed up and identified some twenty-five investigative steps which could have been taken. He also stated that, in his view, virtually no action aimed at identifying the murderer had been taken in 2008, that the operative officers had carried out the instructions received from the investigative officers in a perfunctory manner, and that the investigative and operative departments needed to streamline their methods of communication.
23.  On 28 December 2009 S.J., a new investigator assigned to the case, suspended the proceedings, having uncovered no new leads after completion of further investigative steps.
24.  The proceedings were renewed and then suspended on several further occasions, reference being made to the insufficiency of the measures taken (specifically, on 11 May 2010, 2 April and 22 October 2011).
25.  On 15 April 2013, following the entry into force of the new Code of Criminal Procedure, the applicant was admitted into the proceedings as an aggrieved party and given an opportunity to consult the case file.
26.  On 19 August 2013 the applicant complained to the Minister of Interior that, having studied the file, he found that the entire investigation had been marred by prohibitive delays and inactivity. In his view the competent authorities had, for an extensive period of time, focused predominantly on investigating the probability that his daughter had been stabbed by her husband rather than organising a prompt and comprehensive examination of the objective evidence. A lot of time had been lost. The applicant also gave several suggestions as to further potential witnesses to be questioned, the specific type of the knife which could have been used to stab his daughter, and the circle of persons who might possess such a weapon.
27.  On 2 October 2013 the Deputy Chief of the investigative department of the Poltava Police informed the applicant that no new leads had been uncovered, but his suggestions would be taken into account in further investigation.
28.  On several subsequent occasions the police authorities provided similar answers to further complaints and suggestions made by the applicant and V.K. concerning investigative steps that could be taken.