Earlier this month, it was reported that FBI agents forced someone to unlock their phone with Face ID. This was a somewhat major development, as with Apple's previous Touch ID system, law enforcement couldn't force users to unlock their device.
Now, a report from Motherboard shows that law enforcement is actually being instructed not to even look at iPhones, so as not to lock the device. Apple's smartphones are secured in a way that five failed attempts to unlock it using a biometric method will result in the user having to enter their PIN. This is the same with both Touch ID and Face ID.
This is notable, as law enforcement can't force detainees to give them their PIN, but they can apparently force them to look at their phone to unlock it.
The above slide comes from forensics company Elcomsoft. It also takes a poke at last year's iPhone X launch when Apple's SVP of software engineering Craig Federighi tried to unlock the device with Face ID and failed. This actually happened because multiple people had handled the demo unit prior to the event.
The reason that users can't be forced to provide their PIN or fingerprint is due to Fifth Amendment protections in the United States. People can't be forced to incriminate themselves, and providing information on unlocking a device is seen as doing exactly that.
It's no surprise that police are being instructed to not look at iPhones being confiscated, as there's likely to be evidence on the device that they'll want access to. Moving forward, we can all look forward to more of this ongoing discussion about biometric security, and a user's right to privacy.