The Supreme Court puts email in the same legal category as postcards: little to no expectation of privacy, because everyone along the way can trivially read it.

The Supreme Court puts email in the same legal category as postcards: little to no expectation of privacy, because everyone along the way can trivially read it. Certainly an envelope can be trivially bypassed, but the clear signaling of intent may be enough to sway the legal status of eavesdropping on it.