When everything is working right, an e-mail message appears to zip instantaneously from the sender to the recipient's inbox. But in reality, most messages make several momentary stops as they are processed by various computers en route to their destination.
Those short stops may make no difference to the users, but they make an enormous difference to the privacy that e-mail is accorded under federal law.
Last week a federal appeals court in Boston ruled that federal wiretap laws do not apply to e-mail messages if they are stored, even for a millisecond, on the computers of the Internet providers that process them -- meaning that it can be legal for the government or others to read such messages without a court order.
Details here from Saul Hansell of The New York Times via LexisOne news.