(This is the first of a short series of posts on my new forthcoming article, Applying the Fourth Amendment to the Internet: A General Approach).

  For the last several years, I've been pondering how the Fourth Amendment should be applied to the Internet. The question is difficult in part because to start off you need some sort of a theory as to what the Fourth Amendment means. It's not enough to just follow the terms of existing doctrine, as the doctrine itself is largely indeterminate: What is a "reasonable expectation of privacy," after all? And what makes a search "reasonable"? That doesn't take you very far without some sort of theory about what the Fourth Amendment does.

  Nor does high-level constitutional theory answer very much here. For example, say you're an originalist. It's kind of hard if not impossible to know how that pans out. First, the original public meaning of terms like "unreasonable searches and seizures" remains hotly contested. Second, not only were there no professional police officers at the framing, there was of course no Internet. And if you're a serious originalist, you probably have to rethink the incorporation doctrine, too, which means that you may not even be regulating most police officers any more. So that doesn't necessarily take you very far, either.

  So what to do? In my new paper, I start with an assumption I call "technology neutrality." The idea here is that the Fourth Amendment should apply to the Internet much like the Fourth Amendment applies to the physical world. I therefore start with the role that the Fourth Amendment plays in regulating traditional physical investigations, and I look for ways that the Fourth Amendment should be applied to try to replicate that role online given the very different facts of the Internet. Thus, the goal is "technology neutrality": Ideally, The Fourth Amendment should play the same role regardless of whether a criminal investigation occurs via an investigation in the physical world or whether it occurs via an investigation over the Internet.

  Incidentally, for those well-versed in Larry Lessig's work, my approach ends up being something akin to Lessig's idea of constitutional "translation," although at a more specific level. Whereas Lessig sees the Fourth Amendment as a general protector of privacy, and so envisions the Fourth Amendment as sort of a roaming tool for protecting privacy online, my idea is to look more specifically at how the Fourth Amendment does and does not protect privacy and to recreate both sides of that picture in the new space.

  But why assume "technology neutrality"? To be clear, technology neutrality is just an assumption in my article: I don't actually argue for that position from first principles. If you have theoretical commitments that rule out technology neutrality, then you're just not going to get much out of the paper: It's not the paper for you.

  At the same time, I think the assumption is a helpful one to make for a good practical reason: It's what judges and Justices today think the Fourth Amendment requires. That is, the assumption of technology neutrality captures the general understanding among judges and Justices about how the Fourth Amendment is supposed to be interpreted. This understanding follows a trio of cases in 1967: Berger v. New York, Katz v. United States, and Warden v. Hayden. In all three cases, the Supreme Court had to choose at a conceptual level between the Fourth Amendment as a specific set of protections grounded in history and the Fourth Amendment as a general tool to make that make sure the police don't have too much power. In all three cases, the general view won out.

  Today, every Supreme Court Justice (and every judge I can think of) adopts that basic view. The 1967 view has stuck. The Fourth Amendment is now understood as a tool for requiring "reasonable" police practices in the sense of sensible or desirable ones. Different judges have a different sense of what that means, of course, but pretty much everyone agrees that this is the goal. And implicit in that goal is technology neutrality: If the Fourth Amendment is a general tool for requiring reasonable police practices, then presumably it should require reasonableness in equal degrees regardless of whether the case happens to involve a physical investigation or an Internet investigation.

  So for all practical purposes, we live in a world in which the legal culture and shared understandings of what the Fourth Amendment does require some kind of technology neutrality. You might like it; you might not. But it's the world we're in. What does that actually mean for the Fourth Amendment as applied to the Internet? Stay tuned for that my next post.