In an application filed in the court, NGO, Common Cause, referred to reports about the entry register at the CBI director's residence containing names of "influential" persons allegedly involved in the coalgate scam.
It accused him of scuttling the probe in the "high magnitdue" cases in which 20 FIRs for offences of corruption, cheating, and criminal conspiracy have been lodged and two charge sheets placed in trial court.
The application also referred to the apex court orders to keep the probe free from any interference and to the changing of the status reports of the probe at the instance of polictical executive.
The NGO said it was filing the application in the context of the "extraordinary developments" that have recently come to light.
It claimed there are "incontrovertible" facts in the public domain which lead to the "inescapable conclusion" that it is necessary to remove Sinha from the case for ensuring fair and impartial investigations.
