One more thought about Chris Soghoian’s great post from last week on telecoms and surveillance. The government is able to get an enormous amount of information about your online activity—short of actually reading your e-mails—using tools like National Security Letters and pen/trap orders, which don’t require the showing of “probable cause” required by the Fourth Amendment. And the reason they don’t have to meet that standard is that a line of cases starting in the 70s—misguided in their inception, and ludicrously anachronistic now—established the principle that you don’t have a “reasonable expectation of privacy” in most information  submitted to third parties, like your bank or ISP or phone company.

One of the things Chris included in his post is an objection Yahoo filed to his FOIA request for information about their cooperation with law enforcement. The premise is that it would be a competitive harm to Yahoo if users were really conscious of all the information law enforcement can obtain—that they might be shocked and disturbed and seek out other service providers. Which is to say, they share this information with the service provider on the premise—the expectation!—that it will remain private. Possibly because we no longer live in a world where placing a long-distance phone call routinely requires telling a human operator who you would like to contact, one of many technological facts the law has declined to take note of.