“the email told DOL employees to not delete emails “
No need to send such an email if they weren’t shredding documents.
Wrong, that is a standard message sent out in any organization that may be subject to an investigation. Most of my co-workers routinely delete most of the emails they receive (I always archive all of them so I have a record of client requests in case questions about them arise later).
If my department came under investigation for some reason, we would get an email like this to not delete emails until further notice.