[rietta]

My informal use of private missed the mark in a strict legalistic sense. We are on the same page about email left on the server being subject to subpoena.

For everyone else, unless you use POP3 to download your email to your own personal device and remove it from the server, the email left on the server is not as protected under US law as emails that are fully downloaded to your device. The later requires a search warrant to acquire without your consent.