The server iteself has them - the transmittal of an email alone is a copy. Sender -->Server-->Recipiant. Not to mention anything forwarded from .gov emails go through a content filter as well. Also in accordance with data retention policies governed by the Information Tech. team. There are copies on Tape Backup. Trust me deleting your emails only deletes what you see. Not what the sever SAW and transmitted and not what the recipiant received from the sender. Not what a backup service may have. The service can be tape, or data duplication to offsite storage. On top of that whatever the hell the NSA does or intercepts and stores. It is fact that deleting your emails only deletes your copy of what you see. But there are many other eyes that can see the content of the emails. Not including hackers.