In United States v. Councilman, a 1st Circuit panel held that email intercepted contemporaneously with its transmission did not fall under the protections of the Wiretap Act. The case went en banc and an opinion has yet to issue. Orin Kerr at the VC just wrote a post about recent developments about the issue. He writes:
Congress has introduced a number of statutory amendments to try to settle the matter. The best was introduced on April 28: Senator Leahy introduced S. 936, the E-Mail Privacy Act of 2005, which is a very short and sweet solution. The Leahy bill adds just a few words to the definition of “intercept” under the Wiretap Act to make its already implicit temporal scope textually explicit. It’s an elegant and correct amendment.