U.S. police have reportedly started to unlock dead people’s phones with their fingerprints without probable cause or anyone’s permission.
Dead Men Have Few Rights
Fingerprint readers have made it easier for most people to (relatively) securely lock and unlock their devices without using a complicated password. However, this increase in convenience also means that others will be able to unlock your device more easily if they can physically force you to unlock the device... or if you’re already dead. Forbes reported that police have used dead people's fingers to unlock their phones.
Although fingerprint-locked phones are not ideal from law enforcement’s point of view, because the police need a warrant to unlock them, it hasn't been all bad.
Courts have ruled that fingerprint-locked devices are not given the same Fifth Amendment protections that password-locked devices are given. The main argument is that you can’t claim to have forgotten your fingerprint as you can with passwords. This should apply to other biometric forms of authentication, too, such as face unlocking, iris recognition, voice authentication, and so on.
The one area where police have struggled is when a phone's owner (typically someone attacking others) died, whether it was because they blew themselves up or were shot by the police in an attempt to stop the attackers from causing more harm. At first the FBI tried to get Apple to unlock the devices by suing the company, but eventually the agency backed down, fearing the court would side with Apple and set a precedent.
It seems that now the government has started to simply unlock the devices using the dead people’s fingers. Some argue that although a dead person doesn’t have many rights, that doesn’t necessarily mean that law enforcement should scour through someone’s belongings (or body, for that matter) without some kind of permission, or at least probable cause.
Face ID Isn't Any Better
When Apple introduced Face ID on the iPhone X, it said that the system uses your attention in combination with eye movement in order to unlock the device. However, as some researchers have proven, Face ID could be unlocked with masks or even photos of open eyes. That could make it even easier to unlock iPhones or other devices using face authentication technology.
Fingerprint authentication remains the safest biometric authentication solution, but that doesn’t mean that the form of fingerprint authentication we have today is the best we’ll ever have. The technology to make pulse-detecting fingerprint readers has existed for years, for instance, but it hasn’t been deployed, presumably because there wasn’t much of a need for it. Similar technology has existed for face and eye scanning.
Biometric technology needs to constantly evolve to stay ahead of new attack vectors, whether it’s photos of the fingerprint or eyes, machine learning creating fake voices or faces, 3D printing masks and fingerprints, or even using dead people’s fingers.