Courts take aim at a technology loved by the policeJan 30th 2016 | NEW YORK | From the print edition IN APRIL 2014, three men were shot when a drug deal turned sour on a tree-lined residential street in Baltimore. The city’s police department quickly linked the crime to Kerron Andrews, a dreadlocked 22-year-old, but could not find him at his registered address. Agents used phone records to determine roughly where he was, but instead of going door-to-door until they found him, they opted for something far more efficient: a Hailstorm. Using this, they tracked Mr Andrews directly to an acquaintance’s sofa, between the cushions of which he had stuffed the gun used in the shooting.The Hailstorm is a more advanced version of the StingRay, a surveillance device that operates by mimicking a cellular tower, forcing all nearby mobile phones to reveal their unique identifying codes, known as IMSI numbers. By crosschecking the IMSI numbers of suspects’ phones with those collected by “cell-site simulators” such as Hailstorm and StingRay, police officers can pinpoint people with astonishing precision. The tools have been used to trail suspects to specific rooms in apartment blocks and to find them on moving buses on busy city streets. Developed at first for military and intelligence services, cell-site simulators are now furtively used by federal agencies such as the Federal Bureau of Investigation (FBI) and the Drug Enforcement Administration (DEA) as well as by local police forces across the land.