There's always a law (or not)

Virginia Judge Says Fifth Amendment Protects Passwords Not Fingerprints

"According to The Virginian-Pilot, Judge Steven Frucci ruled that making suspects provide their passwords so police can snoop through their phones is a violation of the Fifth Amendment because it would force suspects to incriminate themselves. But in the same ruling, the presiding judge decided that demanding suspects to provide their fingerprints to unlock a TouchID phone is constitutional because it’s similar to compelling DNA, handwriting or an actual key—all of which the law allows."