An outstanding post on the EFF's Deeplinks blog by my colleague Ernesto Falcon explains the negligent chain of events that led us into the Stingray disaster, where whole cities are being blanketed in continuous location surveillance, without warrants, public consultation, or due process, thanks to the prevalence of "IMSI catchers" ("Stingrays," "Dirtboxes," "cell-site simulators," etc) that spy indiscriminately on anyone carrying a cellular phone — something the FCC had a duty to prevent.
EFF and the ACLU have petitioned the FCC in support of a complaint against the Baltimore police department. The FCC approved this class of devices, after a decade of secret lobbying by their manufacturers, and then failed to undertake any oversight of their use in the field, allowing police to repeatedly, dramatically break their promises about Stingray surveillance.
Police today violate these basic statutory protections when using cell site simulators and thereby disrupting the cellular service of many innocent people. Based on publicly available information, it appears that some cell site simulators utilized today by law enforcement are jamming LTE and 3G services in order to force phones to downgrade to 2G services where they are easily exploited due to legacy vulnerabilities. A study by the Royal Canadian Mounted Police also found that 911 call access can be blocked 50 percent of the time when a phone interacts with a cell site simulator. Testing these devices requires technical analysis but cell site simulators are only legally sold to and owned by law enforcement agencies. Therefore, the FCC is the best suited agency with the legal authority and technical expertise to determine what is happening in Baltimore and potentially across the entire country as wireless surveillance by law enforcement continues to proliferate.
In the past, the FCC faced a similar issue when dealing with cell phone signal boosters. Third parties developed mini-towers that would augment wireless signals in areas with poor coverage. Carriers complained that these devices were operating in their exclusive space and disrupting their service. That was the same problem we see today: signal boosters, like cell site simulators, were interfering with communication services and 911 access. The FCC's response should be the same now as it was then: the agency studied the problem and took steps to resolve it in a public forum.