Satellites were locking in on cell phones owned by members of the nondenominational Protestant church in San Jose, Calif. Their location eventually worked its way to a private company, which then sold the information to the government of Santa Clara County. This data, along with observations from enforcement officers on the ground, was used to levy heavy fines against the church for violating COVID-19 restrictions regarding public gatherings.     

"Every Sunday," Calvary's assistant pastor, Carson Atherly, would later testify, the officers "would serve me a notice of violation during or after church service."

Calvary is suing the county for its use of location data, a controversial tool increasingly deployed by governments at all levels – notably in relation to the U.S. Capitol riot on Jan. 6, 2021. While enabling law enforcement to more easily identify potential offenders, the practice, called "geofencing," has also emerged as a cutting-edge privacy issue, raising constitutional issues involving warrantless searches and, with Calvary Chapel, religious liberty.

"We are in the space between the emergence of this technological practice and courts having ruled on its constitutionality," said Alex Marthews, national chair for Restore the 4th, a nonprofit organization dedicated to the protection of the Fourth Amendment, which protects Americans' rights against "unreasonable search and seizure." 

"Geofencing" often begins with an innocent click. Smartphone apps ask if they can access location to improve service. When users say they yes, they often don't realize that the apps that help them drive, cook, or pray are likely reselling their information to far-flung for-profit entities. This and other information detailing people's behaviors and preferences is valuable for businesses trying to target customers. The global location intelligence market was estimated at $16 billion last year, according to Grand View Research.