With all due respect, the law is not settled. There are numerous arguments that could be made and numerous judges are of the opinion that in order to force someone to use their fingerprint to open a phone? The authorities should have enough evidence to get a warrant to do that AND should pull the absolute minimum of data off that phone that is necessary to determine if that person committed the crime that they are investigating or not.
I.E. no fishing expeditions.
We have gone way too far towards "Law and ORDAH!" today while trampling personal rights to privacy.