This is called the 5th amendment.
1. https://fuscolaw.org/police-cant-force-you-to-unlock-your-sm...
(highlighting is mine)
This decision overrules previous circuit court rulings in California that biometric features were considered testimonies since suspects weren’t verbally giving up their numeric passcodes or passwords.
2. https://jsberrylaw.com/blog/can-police-officers-force-you-to...
The method by which you choose to lock your cellphone can make the difference between being required to unlock it for a police officer or not. Police officers cannot force you to unlock your phone by a testimonial act that reveals the contents of your mind. You can be forced to unlock your phone by a nontestimonial act.
Nontestimonial acts are things like your biometrics, your DNA, etc.