Chidambaram was replying to a question at the launch of a book "Standing Guard - A Year in Opposition" written by him at a hotel in Mumbai.
Home Minister Rajnath Singh on Monday ordered an 'internal inquiry' to probe how files concerning the affidavits filed in the Ishrat Jahan case have gone missing, said informed sources.
Former home secretary GK Pillai had also claimed that there was "political interference" in the case which led to the deletion of reference to Lashkar-e-Taiba from the revised affidavit filed in 2009.
"Tell me which part of the affidavit is wrong, which sentence of the affidavit is wrong. Nobody is alleging against me. The officer who said that he did not know anything about the affidavit, is on record in Guwahati in July 13, 2013 saying that the second affidavit was perfectly justified," said Chidambaram.
"He has changed his view. In a free country, a person is entitled to change his view. The second affidavit was vetted by the attorney general of India. No part of the second affidavit was wrong," he added.
Chidambaram further said: "It was drafted, went to the attorney general, came to me. I, with a compulsive habit of all lawyers, made small 'editorial' changes. This is a habit of all lawyers. Any lawyer would put a comma here and there or strike out a word.
"I don't think any of the files that came to me went back without making a change. That is a habit to make small changes here and there. Then the file went back to the home secretary. The files passed the home secretary's table at least three times."
"And now they say those papers are missing. To whose advantage has the vetted draft gone missing? I want the vetted draft. To whose interest is to say that the draft is missing? There is nothing to hide. I think the mystery has been unravelled now," he added.
On March 10, the home minister had told the Lok Sabha that "two letters from the then home secretary to the attorney general in 2009 have gone missing. The then attorney general had vetted two affidavits regarding the case. Those are also not available".
Last week, Rajnath Singh had announced in the Lok Sabha that an internal inquiry will be conducted in this regard.
The Bharatiya Janata Party (BJP) and home ministry officials had alleged recently that the UPA government did a flip flop over the controversial 2004 shootout in which Ishrat, then a student of a Mumbai college and allegedly a Lashkar-e-Taiba operative, was killed.