Emerging Legal Issues in Compelling the Use of One’s Fingerprint to Open a Phone

• The use of “biometrics” and the compelled opening of private devices  
• Good faith in the execution of a search warrant absent settled law to the contrary  
• The “foregone conclusion” doctrine  
• Communications search warrants for cellphones  
• Compelled use of one’s finger to unlock a cellphone and Fourth Amendment, Fifth Amendment and due process issues 

A separate statement of probable cause, and a request to use reasonable force if necessary, becomes a part of a search warrant when specifically incorporated by reference. An officer’s good faith, absent settled law to the contrary, allows for the execution of a search warrant even if the warrant is later found to be legally inadequate. The use of a suspect’s fingerprint to unlock his cellphone, the contents of the cellphone being non-testimonial, does not violate the subject’s Fifth Amendment privilege against self-incrimination.  

Also, with law enforcement already knowing what the cellphone contains, the “foregone conclusion doctrine” applies, allowing law enforcement to search and seize the cellphone’s contents. A suspect’s due process rights are not violated by a law enforcement officer forcing a suspect to use his fingerprint to open his cellphone when the force used is minimal and insignificant.

Defendant Alfredo Ramirez, as a high school student and into adulthood, preferred younger girls. When in high school (his age is not mentioned), he dated a 15-year-old girl, listed simply as “M.” The couple got pregnant and then married. M, however, was one of 12 children in her family, with at least three younger sisters who are referred to here as Jane Does #2, #3, and #4. The three Jane Does were between the ages of nine and 13 during the events described here. 

During the years Ramirez and M lived together as husband and wife, he often pressured her into having her three sisters sleep over at their house, intentionally excluding M’s brothers. When they visited, Ramirez would take them to places like a boardwalk, a swimming pool, and an amusement park. All three Jane Does eventually complained to their mother, however, that Ramirez habitually came into their ....