We normally assume that no one reads our email but us, and at least 99.9% of the time that is the case. However, the exceptions can turn out to be important:

Technically, email is sent as plain text and may be relayed by many servers before reaching its destination. Server administrators could read any email their servers relay. Think of email as a postcard: anyone who handles it could read it if they wanted to. Ethical administrators, including SSCC staff, will never read other people's email. In practice, the sheer volume of today's email would keep even the most unethical administrators from reading very much of it. But there is some small chance that any given message will be read by someone other than its intended recipient.

Legally, email is frequently subpoenaed as evidence in civil and criminal actions. If SSCC staff receive such a subpoena, and the UW legal department advises us that it is valid, we will have no choice but to comply with it. That means we must produce both what is currently stored on the server and what is on our backup tapes. Since we keep backups of email for one month, that means an email that was stored overnight will be available as evidence for a month, even if you delete it. (Other files are backed up for a year, but not email.)

On the other hand, Wisconsin's Open Records law requires that some communications about University business be retained and produced on request, regardless of their form. This can include email (even email using non-UW accounts, like gmail). See the UW Archives and Records Management site for details.