Voice Prints

Just like fingerprints and facial recognition, advanced technology now allows quick identification using voice prints. We now have a collection of voice prints stored in various databases which can be used to identify us even when we're using burner phones. Because voice prints are not your actual voice but is a biometric representation of it, it presumably skirts the law on wiretapping. The Intelligence Community refers to it as just META DATA.

This dangerous capability basically allows each citizen to be located passively with just voice alone.