The Seventh Circuit just handed down a landmark opinion, ruling 3-0 that the Fourth Amendment protects energy-consumption data collected by smart meters. Smart meters collect energy usage data at high frequencies—typically every 5, 15, or 30 minutes—and therefore know exactly how much electricity is being used, and when, in any given household. The court recognized that data from these devices reveals intimate details about what’s going on inside the home that would otherwise be unavailable to the government without a physical search. The court held that residents have a reasonable expectation of privacy in this data and that the government’s access of it constitutes a “search.”
This case, Naperville Smart Meter Awareness v. City of Naperville, is the first case addressing whether the Fourth Amendment protects smart meter data. Courts have in the past held that the Fourth Amendment does not protect monthly energy usage readings from traditional, analog energy meters, the predecessors to smart meters. The lower court in this case applied that precedent to conclude that smart meter data, too, was unprotected as a matter of law. On appeal, EFF and Privacy International filed an amicus brief urging the Seventh Circuit to reconsider this dangerous ruling. And in its decision, released last week, the Seventh Circuit wisely recognized that smart meters and analog meters are different:
“Using traditional energy meters, utilities typically collect monthly energy consumption in a single lump figure once per month. By contrast, smart meters record consumption much more frequently, often collecting thousands of readings every month. Due to this frequency, smart meters show both the amount of electricity being used inside a home and when that energy is used.”
The Seventh Circuit recognized that this energy usage data “reveals information about the happenings inside a home.” Individual appliances, the court explained, have distinct energy-consumption patterns or “load signatures.” These load signatures allow you to tell not only when people are home, but what they are doing. The court held that the “ever-accelerating pace of technological development carries serious privacy implications” and that smart meters “are no exception.”
This is critical precedent. Last year, roughly 65 million smart meters had been installed in the United States in recent years, with 88% of them—over 57 million—in homes of American consumers; more than 40% of American households had a smart meter. Experts predict that number will reach about 80% by 2020. And law enforcement agencies are already trying to get access to data from energy companies without a warrant.
In this case, a group of citizens called Naperville Smart Meter Awareness challenged Naperville’s policy of requiring every home to have a smart meter, objecting on Fourth Amendment and other grounds. The district court held that smart meter data—despite being collected directly a city utility, not any non-governmental third party—was subject to the so-called “third party doctrine.” In other words, the lower court reasoned that simply because the utility company held the data, it was automatically devoid of constitutional protection.