The probe into coal block allocation scam, which got CBI the sobriquet of "caged parrot" from the Supreme Court and saw the exit of Law Minister Ashwani Kumar over his alleged interference, marked the agency's functioning during a tumultuous year for it.
The passage of the Lokpal Bill by Parliament this year is likely to bring a major change in the working of CBI since the Supreme Court order in the Vineet Narain case in 1997 which had brought in the supervision of Central Vigilance Commission and gave CBI chief a fixed tenure of two years aimed at freeing the agency from the clutches of bureaucracy.
The angry comments of the apex court not only claimed the ministerial scalp of Kumar but also set in motion the modalities for the autonomy of the agency, which according to Supreme Court, has become "voice of its political masters".
The battered government scrambled its best brains in the Cabinet to constitute a group of ministers, which met a number of times, and came up with suggestions to give only "functional autonomy" to the agency.
The financial powers of the CBI Director were given a significant boost but Centre did not agree to give him rank and powers on par with the Secretary of the government of India.
The proposed Lokpal will have powers to refer cases to CBI and keep an eye on the ongoing probe. It will also have powers to transfer officers who will be probing cases referred by it.
Senior officials of the agency agree that new rules of procedure would be required for this change in working.
Even as clamour for giving autonomy to CBI was going on, the agency carried out a major search operation and arrested Vijay Singla, nephew of the then Railway Minister Pawan Kumar Bansal, and Railway Board member Mahesh Kumar.
Although Bansal was not named as an accused in the charge sheet filed by the agency, he had to resign from the Cabinet following the public outcry after the controversy.
Pursuing infamous cases of encounters in Gujarat -- Sadiq Jamal and Ishrat Jahan -- the agency stirred up a hornet's nest as it summoned senior officials of country's snooping agency Intelligence Bureau for examination.
The agency's move to seek records and question senior officers of the intelligence apparatus turned into a bitter turf war between CBI and IB with each trying to defend its action. The matter could only be resolved with the intervention of the Home Secretary.
CBI filed its first charge sheet in the Ishrat Jahan encounter case without naming any of the Intelligence Bureau officials in it. However, the supplementary charge sheets in both the cases are pending.
In the fag end of the year, a CBI court in Ghaziabad pronounced verdict in the sensational murders of Aarushi and Hemraj declaring parents of the 14-year-old girl -- dentist couple Rajesh and Nupur Talwar -- as guilty of the murders and sentenced them to undergo life imprisonment.
Big ticket corruption cases continued to generate heat during the year with agency filing FIR against Aditya Birla Group Chairman K M Birla and former Coal Secretary P C Parakh in one of the coal scam cases. The allegations of any misconduct have been denied by Birla and Parakh.
CBI also registered case against Naveen Jindal, his company Jindal Steel and Power Limited and former coal minister N Dasari Rao in one of the coal scam cases. Both the accused have refuted allegations.