homicide because you are missing that piece of ballistic evidence. that's where you would rely on witnesses or other physical evidence. i know two of the guns that were involved in this case were traced back to the scene of agent terry's murder but i have no knowledge of anything beyond that. that's an fbi investigation and they have not shared any of that information with me nor would they have a reason to. martha: essentially someone knows whether the bullet that lodged in this body, if that were the case, that they would know exactly which gun it had come from if the gun was found at scene and the bullet with us recovered, correct? >> 99% of the time. there are times when the bullet gets so disfigured it's difficult. but if you recover the row joke tile and the firearm there is the ability to make a match. martha: your testimony was interesting in all of this. i know this whole thing has not been easy for you.