Yes. Thumbprints and other forms of biometric authentication have even fewer legal protections than…
Quincy Larson

The best option in this case, as I understand it, is to turn your phone off when you’re in an encounter with an agency. If they turn the phone back on to compel you to put in your fingerprint, that won’t work because iOS requires your password first before Touch ID will work. I don’t know about Android though.