A V Gokak, who served as Telecom Secretary between November 1996 and August 1998, appeared before the JPC headed by Congress leader P C Chacko in connection with the 2G spectrum allocation scam.
A Committee member said he was questioned about the telecom policy being pursued by the then government with regard to cellular operators.
Tomorrow, the JPC will record evidence of Gokak's successor Anil Kumar, who served as Telecom Secretary between August 1998 and February 2000.
The NDA Government had unveiled a migration policy in June 1999 during Kumar's tenure, allowing cellular operators to move from fixed licence fee regime to revenue-sharing model.
The Department of Telecom had told the JPC the migration policy had led to losses to the exchequer to the tune of Rs 43,523.92 crore.
The JPC is examining India's telecom pricing policy 1998-2008, that also covers the period of the NDA government led by the BJP that was in power 1998-2004.
The panel was formed following persistent demands by the Opposition after allegations surfaced of irregularities in the allocation of 2G licences.