Comcast announced a new platform this week called Xfinity Shield that includes the option to let customers turn their routers into motion sensors. “I am not enabling this.

I am also seriously considering replacing my leased gateway with my own equipment, because a device I do not control sitting in my living room measuring the motion of my family is not a feature I asked for,” wrote one customer on the r/Comcast subreddit Some concerns stem from a clause on the support page for the feature, called WiFi Motion, which says Comcast might share motion-sensing data without notifying you if compelled by law. 1/3This page in the Xfinity app shows a live view of motion activity.

Image: ComcastThe feature uses activity in Wi-Fi signals between newer Xfinity Gateways and connected devices to monitor motion in your home; it doesn’t use cameras, capture images or video, or record audio. However, it arrives amid a year of reporting on immigration unrest and how authorities obtain data from private companies like Flock.

”— Meagan SloanThe Verge asked Comcast what data WiFi Motion collects, how long it stores it, whether it shares it, and if so, under what circumstances. “When enabled by the customer, WiFi Motion keeps a record of motion activity within the Xfinity app up to 7 days,” said Comcast spokesperson Meagan Sloan via email.

“Like all companies, should Comcast be served a valid subpoena, court order, search warrant or other lawful legal process, we may be required to disclose information generated by WiFi Motion consistent with applicable law.” But customers also fear the feature could be enabled without their consent and worry about the types of information it was collecting.

We asked whether Comcast could remotely enable it if legally compelled, and whether it could view the data in real time — a scenario law enforcement could potentially use to determine if someone was in a home. Sloan said “WiFi Motion is opt in only by a customer,” and that “No, Comcast does not monitor customers’ motion activity or notifications in real time,” but did not say whether Comcast has the technical ability to do either.

Asked where the data lives, she said the company stores motion activity in its cloud system for up to seven days so users can view recent activity in the app. The data includes motion event information that “indicate when movement is detected between a connected device and the Xfinity Gateway,” Sloan said.

It also shows which Wi-Fi-connected device detected the motion. For example, “Motion detected by LG TV” or “Motion detected by Hallway smart speaker.”