The Justice Department has new rules in place for how federal law enforcement can track specific smartphones using electronic devices known as "stingrays."

The controversial devices basically dupe cell phones by emitting the same kind of radio signal as cellular phone towers to collect information — tricking phones into giving up their electronic signature. Using that data, combined with the strength of the signal, authorities can track the general location of a suspect's cellular device.

The technique has stirred plenty of criticism and the Justice Department has issued new rules for such cases. With the new guidelines, the use of stingray devices will be less abusive and more transparent. The policy now requires the FBI and other federal agencies to get a search warrant before using stingrays.

According to a press release from the Justice Department, the newly issued policy for using cell-site simulators will "enhance transparency and accountability, improve training and supervision, establish a higher and more consistent legal standard and increase privacy protections in relation to law enforcement's use of this critical technology."

The policy applies at the federal level, effective immediately, setting new management controls for leveraging such technology in federal investigations.

Sally Quillian Yates, Deputy Attorney General, further highlights how helpful cell-site simulator technology has been in a wide range of investigations — playing an instrumental role in handling kidnappings, complex narcotics cases and fugitive investigations. For this reason, the Justice Department wants to ensure that federal law enforcement follows proper protocols.

In addition to requiring federal agents to obtain warrants before using stingrays, the new policy also sets some boundaries that limit the type of data that can be collected, as well as for how long. More specifically, stingray-collected information is now restricted to the cellphone's signal direction, but not GPS data, and to the numbers dialed, not the content of conversations, messages, emails or app data.

At the same time, the new policy also forbids storing stingray-collected information for more than 30 days, if officers don't know the number of their specific target — or more than one day if they do. 

Lastly, the new guidelines note that using the technology on aircraft now requires executive-level approval.