Certainly this revelation would have raised its fair share of questions, and it remains to be seen as to whether the hacking was done on a far larger scale compared to what the FBI has revealed, and if that were to be the case, certainly innocent users of TorMail would have had their email hacked along the way. I suppose the politically correct term for such a situation would be “collateral damage”.
One former TorMail user did step forward to say that the malicious code “appeared before you even logged in.” In fact, there should be a large number of TorMail users who were clean and not engaged in any kind of criminal activity whatsoever, and the FBI certainly will not divulge any more additional information.