The Justice Department announced Thursday that law enforcement agencies, including the FBI and DEA, will have to first obtain a warrant before using cell-site simulators known as stingrays.

“Cell-site simulator technology has been instrumental in aiding law enforcement in a broad array of investigations, including kidnappings, fugitive investigations and complicated narcotics cases. This new policy ensures our protocols for this technology are consistent, well-managed and respectful of individuals’ privacy and civil liberties.”

Stingrays are cell phone surveillance tools that mimic cell towers. A mobile phone is tricked into sending location details and other information to the cell-site simulators. Previously, a search warrant wasn’t required to use the Stingrays. Now, probable cause must be found and a search warrant issued before the tactic can be deployed on an individual.

In the announcement, the DOJ also mentioned that the contents of your cellphone may not be gathered using a stingray device.

“Additionally, the policy makes clear that cell-site simulators may not be used to collect the contents of any communication in the course of criminal investigations. This means data contained on the phone itself, such as emails, texts, contact lists and images, may not be collected using this technology.”

If law enforcement agencies continue to use the cell-site simulators without getting a warrant, any case that made use of the tool could easily be thrown out for improper evidence gathering.

A vocal opponent of the surveillance devices has been the ACLU who calls them invasive and illegal. The ACLU has attempted to track the usage of stingrays in the U.S., but says that their usage is so widespread and secret that it’s hard to get accurate figures.

“Law enforcement agencies all over the country possess Stingrays, though their use is often shrouded in secrecy. The ACLU has uncovered evidence that federal and local law enforcement agencies are actively trying to conceal their use from public scrutiny, and we are continuing to push for transparency and reform.”

Linda Lye, an ACLU attorney, told Ars that the change was welcome, but that more could have been done.

This policy change comes two years after former NSA contractor Edward Snowden leaked classified information on government surveillance of U.S. citizens. Since Snowden’s leaks, many Americans have criticized the government for the apparent breach of their Fourth Amendment protections.

Though not yet a central issue, concern over privacy is already an important topic of the 2016 election cycle.

[Photo by Spencer Platt / Getty Image]