The Strasbourg-based court said Russian responsibility for the death of Shamil Said-Khasanovich Akhmadov had been established "beyond all reasonable doubt," and ordered Russia to pay 62,285 euros in damages to his family.
Akhmadov was detained on March 2001 during a raid by Russian forces outside the Chechen capital, Grozny.
His body was found in a field in April 2002 with signs of violent death.
Today's ruling is the latest of several by the court against Russia in cases connected to the deaths of Chechens.
The president of the court, Jean-Paul Costa, said earlier this year that the Russian government was targeted in nearly a fifth of the 90,000 complaints the court still has to process.
Russian President Vladimir Putin has accused it of handing down "political" rulings.
Cases Backed Up
Speaking in Moscow earlier today, Costa voiced hope that Russia would ratify a reform aimed at boosting the court's efficiency.
After talks with the head of Russia's Constitutional Court, Valery Zorkin, Costa said the reform was not "a weapon against Russia."
Russia is the only Council of Europe member state not to have ratified the reform, thereby preventing it from coming into force.
The reform is aimed at allowing more cases to be considered by the court, where they have become increasingly backed up.
The court is the last legal recourse for the citizens of the countries belonging to the Council of Europe.
(Reuters, echr.coe.int, ITAR-TASS)
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