Bhubaneswar, Sept 15: CBI today said the conviction of 13 of the 14 accused in the Graham Staines murder case vindicated the fact that a clean job had been done by the prosecution. "This was a difficult case as we were unfamiliar with the dialect and terrain. We are happy about the verdict," DIG CBI, Loknath Behera said. The CBI was given the task of investigation about two months after the incident. The conviction is an attestation of the fact that the investigation and prosecution teams did their work professionally and a clean job had been done, he told reporters after the judgement. Bureau Report