Because technology moves so quickly, sometimes the law has to play a catch-up game. This is the case for fingerprinting sensors located on mobile devices because, while they enhance security, they do not protect individuals from being forced to give up information in an investigation. By using a biometric fingerprint scanner to open one’s phone for a law enforcement officer, an individual is essentially giving testimony that would not be required of them if they had a passcode.
Police officers can obtain physical evidence during an investigation, which covers fingerprints, so because phone information falls into this category, it gives law enforcement a trove of knowledge about a person. Critics of these biometric fingerprint scanners on devices warn consumers against using Touch ID; while it provides enhanced security in day to day life, it does nothing to protect privacy under government speculation