The Supreme Court has questioned Chief Vigilance Commissioner P J Thomas's moral right to supervise CBI's probe into the 2G spectrum scam. A bench comprising Justices G S Singhvi and A K Ganguly said today that CBI is functioning under the CVC, at that time he was functioning as telecom secretary. The court said it would be difficult for him to objectively monitor as he had justified the action which are being subjected to scrutiny by the court and CBI now.