Facebook told two senators why it tracks users’ locations even when their tracking services are turned off. The lawmakers now say Facebook should give users more control over their data.

Facebook was responding to an inquiry from Sen. Josh Hawley, R-Mo., and Sen. Chris Coons, D-Del., who asked Facebook last month to “respect” users’ decisions to keep their locations private. In a letter dated December 12 that was released Tuesday, Facebook explained how it is able to estimate users’ locations used to target ads even when they’ve chosen to reject location tracking through their smartphone’s operating system.

Facebook said that even when location tracking is turned off, it can deduce users’ general locations from context clues like locations they tag in photos as well as their devices’ IP addresses. While this data is not as precise as Facebook would collect with location tracking enabled, the company said it uses the information for several purposes, including alerting users when their accounts have been accessed in an unusual place and clamping down on the spread of false information.

Facebook acknowledged it also targets ads based on the limited location information it receives when users turn off or limit tracking. Facebook doesn’t allow users to turn off location-based ads, although it does allow users to block Facebook from collecting their precise location, the company wrote.

.@Facebook admits it. Turn off “location services” and they’ll STILL track your location to make money (by sending you ads). There is no opting out. No control over your personal information. That’s Big Tech. And that’s why Congress needs to take action https://t.co/R1LuLcP1LP — Josh Hawley (@HawleyMO) December 17, 2019

“By necessity, virtually all ads on Facebook are targeted based on location, though most commonly ads are targeted to people with a particular city or some larger region,” the company wrote. “Otherwise, people in Washington, D.C. would receive ads for services or events in London, and vice versa.”

Hawley, a frequent tech critic, tweeted the letter, saying it showed Facebook “admits it. Turn off ‘location services’ and they’ll STILL track your location to make money (by sending you ads). There is no opting out. No control over your personal information. That’s Big Tech. And that’s why Congress needs to take action.”

“I appreciate Facebook’s attempts to inform users about their privacy choices. However, I am concerned that these efforts are insufficient and even misleading in light of how Facebook is actually treating user data,” Coons said in a statement. “In their response to our letter, Facebook confirmed that there is no way for users to prevent Facebook from using their location and serving them ads based on that information, even when location access has been turned off."

"Facebook claims that users are in control of their own privacy, but in reality, users aren’t even given an option to stop Facebook from collecting and monetizing their location information," Coons continued. "The American people deserve to know how tech companies use their data, and I will continue working to find solutions to protect Americans’ sensitive information.”