Constitutional experts say that US police could demand that users provide facial data to unlock the new facial recognition tool in Samsung's Galaxy 8 smartphone.The US Fifth Amendment offers protections for passwords and codes no such protections are afforded to biometric security measures such as face scanning.The biometric issue has led to legal battles across the country as police try to gain courts' permission to unlock phones using fingerprints.Now writing in the Verge, legal experts say our faces could be the next frontline issue.”The self-incrimination analysis for biometric and face scanning would be the same as for Touch ID,” says Jeffrey Welty, a law and government professor at UNC-Chapel Hill. “Standing there while a law enforcement officer holds a phone up to your face or your eye is not a 'testimonial' act, because it doesn't require the suspect to provide any information that is inside his or her mind.””If the police already know what's on the device and that the person in question is the owner, the 'foregone conclusion' doctrine may apply,” says Welty.