In a collaborative effort, Apple and Google have developed an industry-standard detection feature called “Detecting Unwanted Location Trackers” (DULT) for Bluetooth trackers. This standard allows users on iOS and Android devices to be alerted if an unknown Bluetooth tracker is monitoring their location.
Both Apple and Google’s location tracking networks are end to end encrypted. Moreover, Apple and Google have refused to put backdoors into their encryption protocols because it’s a massive opportunity for security exploits that could tank their businesses.
If the cops want to find you, they’re probably just going to ask your phone carrier to triangulate you with their tower network, which they’ve been doing for decades. That’s way faster and easier than jumping through hoops to somehow use the Find My or Find My Device networks.