"That is the fundamental question (source of money) which we have been asking and this has not been answered by the agencies involved in the probe," a bench comprising justices B Sudershan Reddy and S S Nijjar said while expressing their dissatisfaction over the probe.
The bench said it was favouring the constitution of SIT as there was no substantial progress in the investigation into the source of money.
"The manner in which the investigation has proceeded since 2008 makes it clear that there has not been substantial progress in the investigation. The speed at which the investigation ought to have been done has not been done," it said.
"Since 2008, you have known that certain individuals for years have some kind of money abroad. Instead of looking into that, you talked about double taxation treaty and this treaty and that treaty. Simple questions you could have asked those individuals were that from where you have got that money which you have so far not answered," it said.
It passed the order after perusing the letter written by him to the Enforcement Directorate expressing threat to his life and his family members.
The apex court also asked the investigators to video-record the statements of the accused and others taking part in the investigation of the case.
During the hearing, Solicitor General Gopal Subramanian told the court that the government was not at this juncture in favour of constitution of SIT to probe the case of black money being stashed away in foreign banks and alleged money laundering by Khan.
Contending that the agencies, currently investigating the case, should continue with their probe, Subramanian said the court may form an SIT to probe the case later if the agencies did not show result. "At this juncture, an SIT should not be appointed. Wait for some more time as the agencies are involved in examining the matter. Any deflection at this point of time will prove far more expensive," the Solicitor General said. He said the government has no objection in principle to video-recording the statements of the accused and witnesses during the investigation process.
Besides the ED probe in the black money case, Khan is also facing a nearly Rs 70,000 crore tax demand notice from the income tax department.
