The Central Bureau of Investigation (CBI) has quietly given an undertaking in writing to the Supreme Court to examine the controversial finance ministry note produced by Janata Party president Subramanian Swamy. It is questioning the role of Home Minister P Chidambaram in the 2G spectrum pricing in his earlier avatar as the finance minister.

The undertaking given by its senior counsel P P Rao in the form of a note came as a surprise as he and the government lawyers vehemently refused for two consecutive days on Wednesday and Thursday to open the 2G scam probe on Chidambaram.

"The new documents, filed for the first time before this court, will naturally be studied and considered by the CBI as usual and may be covered in the next status report," says the note prepared by Rao. He, in fact, read from the note while arguing the case on Thursday, but for unexplained reasons skipped this part of the written submission.

The note caused surprise because it virtually promises that the CBI, which has so far refused to look into Chidambaram’s role, would do so now. But the words "naturally" and "as usual" in the note perhaps suggest that there is nothing extraordinary in examining any evidence that comes up in the course of the investigations.

CBI's counsel Rao took the stand that the ministers take policy decisions for which no "criminality" can be attached as sought by Dr Swamy to ask the CBI to probe alleged criminal conspiracy of Chidambaram with then telecom minister A Raja, who is cooling heels in Tihar Jails in Delhi in the case.