The Supreme Court Wednesday termed the Central Bureau of Investigation (CBI) a "caged parrot" that "speaks in its master's voice".
"It is a caged parrot speaking in its master's voice," a bench headed by Justice R.M. Lodha said, adding: "It's a sordid saga that there are many masters and one parrot."
The court's observations came on CBI director Ranjit Sinha's second affidavit filed on Monday stating that Law Minister Ashwani Kumar and senior officials of the Prime Minister's Office and the coal ministry had made certain changes in the report on the allocation of coal blocks.
The bench also asked the government whether it was contemplating a law to make the working of the CBI independent and insulate it from extraneous intrusion and interferences.
There are other ways of bringing the law, Justice Lodha said, apparently pointing to ordinance route as parliament adjourned sine die Wednesday two days ahead of scheduled.
"The best things would be that such a law is put in place before the next hearing of the case (July 10) so that there would be an impartial and non-partisan independent investigating agency," the judge said.
Pointing to such a scenario, Justice Lodha said: "It would be golden. It would really be wonderful."
The apex court also questioned the credibility of the CBI probe into the allocation of coal blocks and asked for a thorough and qualitative investigation.
Expressing displeasure at the government's interference in the coal allocation probe report, the court said, "the heart of the report was changed on the suggestions of the government officials".
Asking the government to make the investigating agency impartial, the apex court said it needs to be ensured that the CBI functions free of all external pressures.
"If the CBI is not made independent, we will step in," it observed.
It also said that the "job of CBI is not to interact with government officials but to interrogate to find the truth".
The court said the agency "must know how to stand up against all pulls and pressures by government and its officials."