Your Fingerprints. A Key or Testimony? Why It Matters Legally

Many people use the fingerprint recognition feature on newer Apple iPhones and iPads. Consumers view the optional feature, called Touch ID, as a more convenient way to secure their phones versus passcodes. (The feature still requires a passcode, is not foolproof, and is hackable, but let's put those issues aside for now.) Most consumers probably aren't aware of the legal considerations. How the law and courts treat your fingerprints matters... specifically when used to access devices or accounts.

The basic question which the law has not settled, yet, is: are your fingerprints like a key to, say an electronic file cabinet, or are they the equivalent of testimony? The distinction matters when the government forces people to unlock their phones. The Los Angeles Times reported:

"... authorities obtained a search warrant compelling the girlfriend of an alleged Armenian gang member to press her finger against an iPhone... The phone contained Apple's fingerprint identification system... It marked a rare time that prosecutors have demanded a person provide a fingerprint to open a computer, but experts expect such cases to become more common..."

Why this matters:

"... the prevailing legal stance toward fingerprints. Law enforcement routinely obtains search warrants to examine property or monitor telecommunications, even swab inside an inmate's mouth for DNA. But fingerprints have long remained in the class of evidence that doesn't require a warrant... Courts have categorized fingerprints as "real or physical evidence" sourced from the body, unlike communications or knowledge, which cannot be compelled without violating the 5th Amendment... How far can the government go to obtain biometric markers such as fingerprints and hair? The U.S. Supreme Court has held that police can search phones with a valid warrant and compel a person in custody to provide physical evidence such as fingerprints without a judge's permission. But some legal experts say there should be a higher bar for biometric data because providing a fingerprint to open a digital device gives the state access to a vast trove of personal information and could be a form of self-incrimination."

Providing a fingerprint used to be only about identification... identifying a person under arrest. Now, the same fingerprint can also be used to access electronic documents:

"... the act of compelling a person in custody to press her finger against a phone breached the 5th Amendment's protection against self-incrimination. It forced [the defendant] to testify —without uttering a word — because by moving her finger and unlocking the phone, she authenticated its contents."

Legal experts disagree about whether fingerprints are the equivalent of keys or testimony:

"... Albert Gidari, the director of privacy at Stanford Law School's Center for Internet and Society, said the action might not violate the 5th Amendment prohibition of self-incrimination... George M. Dery III, a lawyer and criminal justice professor at California State University, Fullerton, likened the warrant to the government's request for a key..."

Your opinions? Thoughts?