Police in Florida have, at the request of the US Marshals Service, been deliberately lying to judges and defendants about using a surveillance tool to track suspects.
Officers using so-called stingrays have been routinely telling judges, in applications for warrants, that they obtained knowledge of a suspect's location from a "confidential source" rather than disclosing that the information was gleaned using a stingray.
Five emails written in April, 2009, were obtained today by the American Civil Liberties Union coppers are shown discussing the deception.
The ACLU wrote a blog about how the emails show that concealing the use of stingrays deprives defendants of their right to challenge unconstitutional surveillance and keeps the public in the dark about invasive monitoring by local police.
"And local and federal law enforcement should certainly not be colluding to hide basic and accurate information about their practices from the public and the courts," the blog said.
Stingrays, also known as IMSI catchers, simulate a mobile phone tower and trick any nearby mobile devices into connecting with them, thereby revealing their location.
When mobile phones—and other wireless communication devices—connect to the stingray, the device can see and record their unique ID numbers and traffic data, as well as information that points to the device's location. By moving the stingray around, authorities can triangulate the device's location with greater precision than they can using data obtained from a fixed tower location.
The US government has long asserted it doesn't need a probable-cause warrant to use stingrays because the devices don't collect the content of phone calls and text messages.
The ACLU and others say that Stingrays should require a warrant. By not obtaining a warrant to use stingrays, however, police can conceal from judges and defendant's their use of the devices and prevent the public from learning how the technology is employed.
But the emails released Thursday show police in Florida are going even further to conceal their use of the equipment when they seek probable cause warrants to search facilities where a suspect is located, deceiving the courts about where they obtain the information.