In a recent opinion piece at wired.com, Bruce Schneier criticizes the “expectation of privacy” test that is used to interpret the fourth amendment of the United States. He notes that this test is dangerous, because “the whole ‘expectations’ test is circular -- what the government does affects what the government can do”.
The American constitution guards citizens against unreasonable searches and seizures. This right is interpreted by looking at the individual’s subjective expectation of privacy, as well as objective societal expectations. Schneier’s questions and criticisms are equally valuable to Canadians, as the American test for the fourth amendment is similar to that being used for section 8 of the Canadian Charter of Rights and Freedoms, the right to be secure against unreasonable search and seizure.
The Supreme Court of Canada interpreted this right in the criminal case R v Tessling. Before one can even ask whether the government has violated someone’s privacy, we must determine whether the subject matter of the government’s action was private. This is where the reasonable expectation of privacy test comes in, to draw the line between the private and public sphere. First, the individual must subjectively expect that the subject matter in question is private, and secondly, that belief must be objectively reasonable. In Tessling, the court applied the test to police who had used infrared imaging technology to detect houses with an unusual amount of heat emanating from them. Using this technology, along with other evidence, they were able to establish probable grounds that illegal narcotics were being grown on a specific property. When the property owners stated that this infrared data should be excluded from the evidence as private, the court ultimately concluded that they did not have the reasonable expectation of privacy in their property's thermal information.
Sidestepping the difficult debate about searches and seizures, this case shows how the test is designed to be flexible to changing circumstances. The entire common law system is based on the notion that society changes, both culturally and technologically, and that judges have a role in ensuring that old laws stay relevant to new contexts. To that degree, a reasonable expectation of privacy test serves its role. Schneier criticizes this approach, however, by pointing out that “today's technology make it easier than ever to violate privacy… but it doesn't necessarily follow that we have to violate privacy.” Schneier's criticisms are taken in good faith, but it is difficult to imagine how to define privacy without a technological context. Young people are growing up in the age of online social networking, and for better or for worse their boundaries of privacy are different from the generation before them. It is difficult to imagine a society that will protect information that the same society does not expect to maintain as private.
Schneier identifies a much more problematic aspect of the test in examining how the government itself can erode the expectation of privacy, and change a search from unreasonable to reasonable. True, a government would not be able to override a societal consensus about privacy with an arbitrary or sudden shift in policy. But as the example of warrantless wiretapping illustrates, the ability for the U.S. government to justify the program makes the application of the "expectation" test unclear:
In Katz, the Court ruled that the police could not eavesdrop on a phone call without a warrant: Katz expected his phone conversations to be private and this expectation resulted from a reasonable balance between personal privacy and societal security. Given NSA's large-scale warrantless eavesdropping, and the previous administration's continual insistence that it was necessary to keep America safe from terrorism, is it still reasonable to expect that our phone conversations are private?
Certainly, with the U.S. government boasting their wiretapping program as a tool to fight terrorism, it is not clear that Americans can reasonably continue to expect that their phone conversations are private. Moreover, by invoking the rhetoric of security, it is not even clear that Americans expect that their phone conversations should stay private. It may offer some relief that a poll of Americans indicates that most Americans believe the government should obtain a warrant in order to wiretap a phone conversation. But Schneier notes that the court’s test “isn't based on anything like polling data; it is more of a normative idea of what level of privacy people should be allowed to expect, given the competing importance of personal privacy on one hand and the government's interest in public safety on the other.”
Schneier's criticism of the current legal scheme is well-founded. It is difficult to determine if the test should shift towards permanent ground or public opinion. But since the test is supposed to protect citizens from unreasonable government searches, it becomes important to find a way to protect the test itself from the government.