Highly placed sources in the agency said that the 13-page reply of Maharashtra Governor K Sankaranarayanan was examined and the CBI was now planning to seek a review in light of the grounds on which the permission was declined.
The governor had cited "insufficient evidence" as one of the reasons for refusal of permission recently, but the CBI sources said that the proof, which had already been submitted to the local court in Mumbai, was enough to grant the sanction, they said.
The investigating agency also plans to inform the court about the governor's decision and agency's effort to seek the permission, the sources said.
Chavan, who had to resign from the post of the chief minister of Maharashtra after the scam surfaced, was among 12 persons chargesheeted by the CBI in connection with the case.
The former Chief Minister had challenged his inclusion in the chargesheet, saying no sanction for prosecution was taken from the Governor whereas CBI countered it by saying since he was a former minister at the time of being chargesheeted, there was no need for sanction.
The court, however, directed the agency to get the sanction for prosecution.
Later, CBI approached the Maharashtra governor seeking the sanction which was rejected even though the agency had made a detailed submission for it.
The CBI had alleged in its charge sheet that Chavan had increased the floor space index of the controversial Adarsh Society in Mumbai in exchange for two flats to his relatives.
Chavan's mother-in-law Bhagvati Sharma, sister-in-law Seema Sharma and father-in-law's brother Madanlal Sharma have flats in the society.
Chavan also asked the society to take 40 per cent members from civilian category, when it was originally meant only for war veterans, CBI has alleged, adding that Chavan played a key role in the scam.
CBI has filed chargesheet against Chavan and 12 others for criminal conspiracy, cheating and criminal misconduct under Indian Penal Code and also under Prevention of Corruption Act.
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