Earlier quoted context omitted.
If you turn off your iPhone, you can't use it again without entering your password, and you would have to do that consciously. On the other hand, your phone could otherwise be unlocked with just your fingerprint.
Is there a way to know Touch ID is available, but can't be used because the device was just rebooted? Or does it act like there's just a password?
I don't know the verbatim message, but it says something along the lines of "Passcode is required to enable Touch ID"