Cyphers concluded that “Fog’s service allows police to track people’s movements”—both broadly and specifically—”over long periods of time.” Police can start by searching everyone in an area and then toggle to the device search to find out where people connected to those devices “live and work.” This, Cyphers wrote, allows local police the same capability federal agencies have when serving geofence warrants to Google, without needing Google’s permission or a warrant.
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