IANAL but this seems to be pretty common all across the world. The usual recommendation is to put your phone in "lockdown" mode if there's any suspicion you may get arrested. This prevents the phone from being unlocked with biometrics and require pin.
You can do this either by restarting or turning off your phone, or a button combination (power + volume up on my android) and selecting lockdown.
Also for iPhone:
If you press just the side button/lock button five times in quick succession, it will also go into lockdown mode and can only be unlocked with a pin. A little easier to covertly do as it’s just a button mash before you get nabbed.
At least on my stock Android Pixel you cannot use biometrics to unlock after a restart. So if you just hold down the power button to shut off the phone it would require a pin after booting.
If you're using Android you can automate lockdown mode using Tasker so that it can it can be enabled "passively". For example, on my phone lockdown happens after: too many incorrect access attempts (bad biometric or passcode), any Bluetooth disconnects, any sudden shakes or jolts. So if someone takes my phone away from me, takes my phone from my car, or if I turn off my watch then lockdown. If someone fails to unlock my phone: photo taken, synced to cloud, phone lockdown. If my phone gets tapped, set down a little to roughly, or I get thrown to the ground or against a car with my phone in my pocket then lockdown. Sure, it means biometrics is often disabled on my phone, but now I find that reassuring.
If you close your eyes the face id won't work. I suppose the police could force you to open your eyes somehow but if they are going to do that they can force you to put your pin in too.
they don't have to torture you. They can pressure you in all kinds of ways. Even mere threat of locking you up and throwing away the key would get you to unlock your phone.
I'm not a legal expert but as far as I know if the police are arresting you they can compel this in New Zealand. There is no difference in unlock methods. People get charges for not complying.
A person exercising a search power in respect of any data held in a computer system or other data storage device may require a specified person to provide access information and other information or assistance that is reasonable and necessary to allow the person exercising the search power to access that data.
Effectively, if the police search is otherwise legal, then they can compel you to unlock your phone. If you don't, you can get up to 3 months in prison:
178 Offence of failing to carry out obligations in relation to computer system search
Every person commits an offence and is liable on conviction to imprisonment for a term not exceeding 3 months who fails, without reasonable excuse, to assist a person exercising a search power when requested to do so under section 130(1).
A specified person may not be required under subsection (1) to give any information tending to incriminate the person.
But clarifies in 130 (3):
Subsection (2) does not prevent a person exercising a search power from requiring a specified person to provide information or providing assistance that is reasonable and necessary to allow the person exercising the search power to access data held in, or accessible from, a computer system or other data storage device that contains or may contain information tending to incriminate the specified person.
So basically, if the data used to unlock your phone can incriminate you, you don't have to provide it. But that doesn't protect you from incriminating evidence on your phone.
So I guess the moral of the story is that if you're a drug dealer, make sure your phone password is "ImADrugDealer" and then you can't be forced to provide that information. But I guess they can force you to unlock it without telling them the password? so I'm not sure what section 130 (2) had in mind.
This feels weird to me. If your password is "ILikePotato", which is then used to decrypt a text file that contains "IStoleTheMonaLisaAndReplacedItWithAPhotocopy", how is that any different in terms of "incriminating yourself" than if it was the other way around..?
And if you actually forgot your password, that's 3 months jail for you, because they'll hardly believe you? Better have just one so you'll surely remember!
I wonder, if you use special markings to keep track of your illegal doings, and one of your notebooks is found during a search, are you required to assist in deciphering the contents of it? That's basically the same thing as decrypting your hard drive.
Forcing someone to unlock their phone after being arrested for something unrelated, is no different than them forcing you to unlock your house so that they can rifle through your stuff looking for additional things to charge you with. It's immoral, and it should be illegal. The government found new ways to circumvent people's rights with the digital world, and they're walking all over people's liberty.