The Supreme Court has eschewed the “reasonable expectation of privacy” test in its most important recent Fourth Amendment cases. It’s not certain that the trend away from the so-called “Katz test,” largely driven by Justice Scalia, will continue, and nobody knows what will replace it. But doctrinal shift is in the air. Courts are searching for new and better ways to administer the Fourth Amendment.
A good example is the Tenth Circuit’s decision last week in U.S. v. Ackerman. That court found that opening an email file was a Fourth Amendment “search,” both as a matter of reasonable expectations doctrine and the “distinct line of authority” that is emerging from the Supreme Court’s 2012 decision in U.S. v. Jones.
Here are the facts: AOL scans outgoing emails for child porn by comparing hashes of files sent through its network to hashes of known child porn. When it becomes aware of child porn, it is required by law to report them to the National Center for Missing and Exploited Children. NCMEC is a governmental entity and agent. (That point takes up the bulk of the decision; Congress has made huge grants of governmental power to the organization.) NCMEC opened the file without a warrant.