The Colombo-based court convicted Emil Lamahewage, the Prison Commissioner, but acquitted co-accused police commander Moses Rangajeewa for lack of evidence.
The judges read the sentence and ordered to take Lamahewage to the same prison where the massacre happened.
According to Sri Lankan media, Lamahewage told judges that the case against him was “built on a political conspiracy.”
A riot erupted inside the Welikada prison in the capital Colombo when police started a crackdown against drugs in November 2012. Troops were called in to restore order and witnesses claimed eight of the 27 killed inmates were called out by name and executed. The clash left nearly 50 people injured.
According to court documents, the crime scene was later manipulated to make it look as if the victims attacked the guards.
The mass killing triggered global condemnation of the government of Mahinda Rajapaksa, who is the current prime minister of the island nation.
It was the worst mass killing since the massacre of inmates at the same prison that took place during the 1983 ‘Black July’ pogrom against the Sri Lankan Tamil minority in Colombo.
Only 20 of the 73 Tamil political prisoners survived an organized attack by Sinhala prison officials and other convicts. Nobody was processed for the death of the 53 inmates.