University police departments have been using a new tool to keep a close eye on students and faculty – mobile phone detectors. Devices like the PocketHound or Wolfhound can track mobile phones from 150 feet away indoors, and up to a mile away outdoors. Some of these devices can even locate phones that are in standby mode, because they identify the phone's operating frequency, not its phone number or service provider. These phone detectors are often used in prisons to discover contraband phones, but now appear to be gaining in popularity among campus police.
These new phone detectors work differently than traditional wiretapping or phone tracking methods, so police are free to use them without a warrant. Berkley Variatronics Systems, manufacturer of the $2,400 Wolfhound-PRO, advertises that the device “does NOT intercept or 'listen-in' on any phones calls making it fully legal and the tool of choice for law enforcement trying to avoid sluggish court orders and search warrants.”
Police departments have worked to keep their use of these devices a secret. A spokeswoman for the Baltimore Police Department told the Wall Street Journal that the department “can’t disclose any legal requirements associated with the use of this equipment.” A recent article in the Daily Texan reported that University of Texas Police used “advanced tracking techniques” to locate phones, even if the phones are dead, but did not disclose details about the new technology.
Police have been quick to embrace new surveillance technology like phone detectors and “stingray” cell site simulators, and have put them into use before any laws governing the devices' use have been passed. “That’s something that law enforcement has to account for, that they’re putting secrecy ahead of public safety,” David Rocah, senior staff attorney at ACLU of Maryland, said. “You cannot say that these things are critical to public safety and then sell out public safety in the same breath.”