a) put a bug in your phone
b) root through your discarded garbage
c) point a heat-detecting device at your walls
If you guessed "b," you're absolutely right. Once it's left your house, your trash is fair game for any inquisitive police officer who happens down your street. According to Monday's 5-4 Supreme Court ruling, however, police are required to get a warrant if they're interested in just how much heat your house is putting off.
The case came up in 1992, when police used just such a method to investigate Danny Lee Kyllo, a homeowner in Florence Oregon. Police were tipped off that Kyllo, who lived next door to a man suspected of growing marijuana, might be planting a bit of the stuff himself. So the cops used a new technique to identify hot spots (where plant lights were located) on the walls of Kyllo's home. The result? Kyllo was arrested and convicted (which has now been overturned) for growing marijuana.
The technological aspects of Kyllo's case stretch the boundaries of the Fourth Amendment, which reads: "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated. No warrants shall issue, but upon probable cause... and particularly describing the place to be searched and the persons or things to be seized." As it depended on data collected by a high-tech device, Kyllo's case could not be solved by the traditional idea of concrete boundaries. The police used a heat-seeking device to measure temperature inside and outside the walls; there was no way to determine what evidence, exactly, fell inside the house or outside the house.
That uncertainty divided the Court, and brought up more questions than could be answered in one opinion.
Robert Bloom, a professor of law at Boston College, spoke with TIME.com Monday afternoon.
TIME.com: Does this ruling surprise you?
Robert Bloom: It does. Largely because the court has been pretty clear that evidence collected outside the home is okay, but anything inside requires a warrant. And you can argue that this heat was on the outside of the house.
The majority formed an unusual coalition today — Justices Scalia, Thomas, Ginsburg and Breyer joined Justice Souter. What do you think prompted Scalia and Thomas to side with their more liberal colleagues?
Justices Scalia and Thomas seem to recognize the sanctity of the home, and are interested in protecting citizen's reasonable expectations of privacy. For historical reasons, Scalia was making a decision that makes him look like he's in favor of individual rights, whereas in fact, he is primarily interested in upholding the letter of common law.
There was another surprise, of course, on the dissenting side. Justices O'Connor and Kennedy swing and they're hard to pinpoint, and Rehnquist ruled as expected. But Stevens' dissention against the majority is a surprise.
What do you think prompted Stevens' defection?
Stevens got into the technological aspects of the case and said, largely, this information is coming from the outside of the home, as heat waves coming off the walls. I get the sense he'd like to limit these protections to the home itself, not to something coming from the house. It didn't help that he also had some problems with the majority language.
Just out of curiosity, could a policeman arrest you if they see a marijuana plant growing in your window?
No, but he could use the information about the plant to come back with a warrant. It's perfectly legal for the police to respond if a homeowner's shade is up and you can see a plant from the road without using an enhancement device, like binoculars or a special camera.
Do you think this ruling is consistent with the Court's previous rulings on privacy and searches? (The Court also requires search warrants for phone and household "bugging" devices.)
In a sense this ruling is perfectly consistent. The Supreme court has been very strict about maintaining citizens' expectation of privacy within the home. Once you leave those walls, though, the rules are much more malleable.
This case seems to be another example of the Court trying to deal with technological advances within the context of existing law. Has the electronic age altered the position of the Court as far as the Fourth Amendment is concerned?
I think the Supreme Court, at least with regard to technological advancements, (except for things that have been around: cameras) has not dealt very much with technological advances. There are a whole slew of Fourth Amendment issues surrounding computers, for example. There are issues of whether it's okay to search a hard drive but not disks — or vice versa.
Increasingly, we're going to see the Court ruling on the admissibility of evidence collected with sophisticated devices. I think we'll look back on this case as part of the Court's introduction to that era.