"The Courts have said that an un-read, e-mail stored on a server, is like an envelope containing a letter. A warrant is required to do anything other than examine the header (i.e. the face) of the letter.
Once read, it is no longer like a letter, it is business correspondence, and a warrant is no longer required."
That hasn't reached the Supreme Court, has it?
In light of their recent rulings in support of protections from electronic surveillance, I expect the Supreme Court will overturn the lower courts which have been giving the OK for warrantless email access.