According to The Wall Street Journal, a three-month-old decision by DNI Michael McConnell has dramatically expanded intelligence agencies’ access to domestic surveillance images from spy satellites. There are a couple of interesting legal questions here, as the WSJ article notes. The first is whether routine domestic intelligence use of satellites developed by the military runs afoul of the Posse Comitatus Act. The other is how and whether the Fourth Amendment limits satellite surveillance. The courts have, to date, not regarded aerial observation by planes as a “search” for Fourth Amendment purposes, under the plain view doctrine. The sensible intuition here is that you have no protected privacy interest in what can be observed without entering your property: If you’re foolish enough to put your marijuana crop in front of an open window—or in a field that can be spotted by someone flying overhead—you can’t complain if the police notice it. But the analogy to casual observation begins to seem awfully strained when we consider the potential of satellite imaging to create a perpetual record of whole regions of the country, allowing anyone’s comings and goings to be tracked. This may, then, present a problem of what Lawrence Lessig has called “Fidelity in Translation”: Constitutional rules create a balance between conflicting interests—citizens’ need for privacy and law enforcement’s need to gather information—but as technology changes, the application of the same rule may produce a very different balance of interests. The question, then, is how, whether, and when fidelity to the Constitution may mean discarding the original rule in order to preserve the original balance.
Update: Nick Beaudrot, writing at Ezra’s, suggests the that ruling in Kyllo may provide precedent for limits on high-tech searches. I’m a bit less sanguine. (Incidentally, a very short history of 20th century search-tech ruling I wrote a sidebar for a longer Reason feature may be helpful here.) The Kyllo ruling concerned activity inside a private residence, and suggested that technology could not be used (without a warrant) to non-intrusively gather information that could otherwise only be obtained by physical intrusion into the home. And this may indeed bar the use of, say, infrared imaging tech on spy satellites. But on my reading, anything that might, in principle, have been observed by a human being on the ground outside the four walls of the specially-protected space of the home is still fair game. So there’s still little reason to think that the courts are prepared to recognize that permanence and searchability make a difference make a difference in the status of observations in the ordinary visual spectrum.
Update II: Per the comments, I should clarify I’m not saying current tech can literally produce a high-res, 24/7 movie of the whole country. But taking that as one extreme and casual observation by a cop on foot as the other, it’s clear that there’s a gradient of permanence and ubiquity along which such “plain view” surveillance can fall. At some point, there’s a real and qualitative change in the kind of privacy we enjoy.