R. Mohan, a former Income Tax official, was appointed as Vijayan's private secretary in March when the election model code of conduct was in force.
"Mohan, as additional director (investigation) of Income Tax, in 2007 probed corruption charges against Vijayan on the orders of the Kerala High Court. Vijayan was then the CPI-M state Secretary and petitioner T.P.Nandkumar had sought information on sources of his income," said Neelakantan, a former leader of the Aam Aadmi Party (AAP) in Kerala.
"In 2007, Mohan submitted a report in the High Court giving Vijayan a clean chit. The clean chit was based on an affidavit submitted by Vijayan himself. But in 2008, in a letter to the Additional Solicitor General, he said that the Central Board of Direct Taxes was still looking into the charges," said Neelakantan.
"So far Chief Minister's private secretary was usually a senior state committee member of the CPI-M. This is for the first time that a bureaucrat has been appointed to the position. That's where the suspicion arises that this is nothing but a quid pro quo deal for the services that Mohan rendered to Vijayan," added activist Shajahan.
The two activists said they have already submitted a RTI query for details of the clean chit to Vijayan and will also approach the CBDT soon.
"The CPI-M was supporting the first UPA government in 2007-08 and there is every chance of the case having been swept under the carpet. We will bring it out," they added.
When contacted, Mohan told : "It's their right to speak. I do not have anything to say."
( With inputs from IANS )