The European Court of Human Rights (ECHR) has ruled that while it had insufficient evidence to conclude there was Russian state involvement in the 2009 abduction and murder of human rights activist Natalya Estemirova, Russian authorities failed to properly investigate the killing.
The court found Russian officials also undermined the ECHR's proceedings in the case, brought by Estemirova's sister, by refusing to comply with evidentiary requirements.
Estemirova's daughter and the rights group that her mother worked for both expressed disappointment with the court's failure to point a finger at Russian officials they believe are responsible.
The 51-year-old Estemirova worked for the Memorial human rights group and documented extrajudicial killings, kidnappings, and other abuses by law enforcement officers in the southern Russian region of Chechnya before she disappeared in Grozny.
Her body was found hours later in neighboring Ingushetia with gunshot wounds to the head and chest.
Many of Estemirova's cases exposed "specific crimes allegedly committed by insurgents and law-enforcement personnel of the Republic of Chechnya," the court noted.
Chechen leader Ramzan Kadyrov has been accused by local and international rights groups of overseeing abuses against perceived opponents, roundups and summary procedures by law enforcement, as well as numerous intimidation tactics since taking power with Kremlin backing in 2007.
Russian and international rights groups have criticized Russia for failing to bring anyone to justice for the 12-year-old killing.
Russian investigators charged an alleged militant, Alkhazur Bashayev, in the killing in 2010 and ordered his arrest, but he has not been found.
Estemirova's sister, Svyetlana, who brought the ECHR case, argued that Russian officials were behind the abduction.
The ECHR ruled that "the applicant had not made out a case that Natalya Estemirova, had been abducted by state agents, and the evidence did not support the state involvement in her murder."
Estemirova's and many other high-profile killings of rights advocates and political opponents of Russian President Vladimir Putin and his apparatus have gone unsolved in the two decades he has held power.
The ruling said the court "did draw parallels with similar well-known cases such as those of Anna Politkovskaya and Yury Orlov in Russia," two prominent critics who were killed in the past.
"However, it was unable to accept the applicant's argument that this was a prima facie case of abduction by state agents. It did not switch the burden of proof to the government."
But the ruling said the court "concludes that the authorities failed to investigate effectively the abduction and killing of Natalya Estemirova."
It also urged Russian officials to find Estemirova's killer or killers.
The ECHR ordered Russia to pay 20,000 euros ($23,600) in nonfinancial damages.
Russia did not officially respond to the ruling by the ECHR, many of whose judgments have been ignored in the past by Russian officials.
Rights groups have chronicled more than a decade of abuses since Kadyrov took over the restive region of Chechnya following two wars against separatists after the Soviet Union fell in 1991.
Kadyrov denies the allegations.
Estemirova's daughter, Lana, expressed disappointment with the ruling.
"I am glad that the court found that there was no proper investigation, but otherwise this is an extremely disappointing judgment," she said in a statement.
"It was a catch-22 situation, as the court concluded there was not enough evidence of the Russian authorities' complicity in my mother's murder, but they didn't submit enough evidence to the court. This is no way to produce a fair judgment."
Memorial, whose board member Oleg Orlov had directly accused Kadyrov of responsibility for the killing and was prosecuted for slander but then acquitted, also expressed disappointment over the ruling.
"Memorial regrets that the ECHR did not acknowledge the responsibility of the authorities in the death of Natalya Estemirova," it said.