Naperville Smart Meter Awareness v. City of Naperville

The City of Naperville, Illinois (the city) (defendant) modernized its electrical grid and upgraded electric customers’ residential energy meters from analog meters that collected energy-consumption data once per month to digital smart meters that collected energy-consumption data every 15 minutes. The frequent data collection, coupled with the unique energy-consumption patterns of various home appliances, made it possible to determine the appliances used in a residence and when those appliances were used. That information could be used to infer information about activities taking place inside the residence, when residents were home or away, and when residents were sleeping or eating. The digital smart meters were new technology that had not yet been widely adopted, but their use benefited utilities and consumers by reducing costs, encouraging energy efficiency, and increasing the grid’s stability. Although city electric customers could not opt out of the smart-meter program, the city informed customers that their data would not be provided to law enforcement without a warrant. The group Naperville Smart Meter Awareness (Smart) (plaintiff) sued the city in federal district court, asserting that the data collection from the smart meters was an unreasonable search that violated the Illinois Constitution and the Fourth Amendment to the United States Constitution. The district court dismissed Smart’s complaint without leave to amend, and Smart appealed.