The agency had registered a preliminary enquiry after purported tapped conversations of its lawyer A K Singh and Unitech Managing Director Sanjay Chandra an accused in the 2G spectrum allocation scam case were aired on a news channel.
During its probe, the CBI has not found any evidence which indicates receipt of any illegal gratification by Singh and believes it was a case of indiscreet talk by him for which departmental action could be recommended, CBI sources said.
Meanwhile, the agency has received the report from Central Forensic Science Laboratory (CFSL) about the previous CD purportedly having conversations between its prosecutor and Chandra, who is an accused in the 2G Telecom spectrum allocation scam.
The CFSL has said the conversations are "untampered". However, in the absence of voice samples of Singh and Chandra, it could not authenticate whether the voices in the recordings are of the duo, they said.
Singh, who was removed as prosecutor after surfacing of tapes, has reportedly told investigators that there was nothing unusual in discussing case-related facts with the defence and it is a normal practice as far as it does not adversely affect prosecution's case, they claimed.
Unitech had rejected the allegations, saying Chandra had never met the prosecutor in the 2G case outside the court or had any phone conversation with him.