I have blogged a few times about the Ninth Circuit's recent decision in United States v. Ziegler, which reached the plainly erroneous and very troubling conclusion that a workplace monitoring policy in a private-sector workplace eliminates all Fourth Amendment rights. I blogged about Ziegler's petition for rehearing a month ago, and shortly thereafter the Ninth Circuit called for a response from the United States. Last week the government filed its response, which I have posted here: Appellee's Response to Petition for Rehearing and Rehearing En Banc.

  The government's brief reflects a basic misunderstanding of the Fourth Amendment, and in particular the meaning of the reasonable expectation of privacy test. The government's brief assumes that a reasonable expectation of privacy is all about what I have elsewhere termed the probabilistic model — that is, the chances that something will remain private. Thus, the government imagines, whether a person has a reasonable expectation of privacy is inherently fact-sensitive, and all you need to do is look to the very specific circumstances and see if based on the context it was reasonable for someone to expect privacy. From that perspective, whether a case involves (say) government or private-sector employment is only relevant to the extent actual workplace policies are different.

  But that's simply not how the Fourth Amendment works. The "reasonable expectation of privacy" test is actually a system of localized rules: the phrase is simply a label, and what it actually means depends on the specific context as determined by the Supreme Court's cases. The Supreme Court has decided dozens of cases interpreting the reasonable expectation of privacy test, and those cases offer specific interpretations for lower courts to use. As a result, the actual meaning of the Fourth Amendment is highly localized: "reasonable expectation of privacy" means different things in different contexts, and usually has nothing to do with the probability that a reasonable person would expect something to remain private.

  That difference is critical here, because the Supreme Court has handed down different localized rules for Fourth Amendment rights in a public employment context and in a private employment context. I realize it seems strange at first, but it's basic hornbook law: the doctrinal test for whether there is a "reasonable expectation of privacy" in a private workplace is simply different from the test in a public-sector workplace. It's not because the workplaces are inherently different, but because the U.S. Supreme Court has decided to regulate the two environments using different legal rules. In a nutshell, the private sector rule is that there is an REP unless the workplace is open to the public; in the public sector, there is no REP unless the employee is afforded a space that is not shared by other employees or subject to regular access by other employees. Two different contexts, two different legal rules.

  (Incidentally, if you're interested in learning more about this, I should have a new draft up in about 2 weeks explaining exactly how the Supreme Court uses these different tests to create localized Fourth Amendment rules, all under the "reasonable expectation of privacy" rubric. Stay tuned.)