Pretty sure this has always been the case. Giving up a piece of information like a password has always been considered self-incrimination and therefore is a violation of your rights.

This is why you should get rid of face unlock, body unlock, fingerprint unlock etc. on your phone and just use a passcode. The police can compel you to unlock your phone using those other methods, because those aren't information locked in your head.

Since this relates to laws, it should be noted that this is related to the US, and that other countries may treat the issue completely differently.