Ghostwheel
Pyrrhonist
With my friend, it's her finger pattern not fingerprint. (Put your finger on the phone and trace out a pattern) The phone doesn't care who you are. Face recognition is quite good because no matter how identical you are, the distances between recognition points will vary at some places, but the average college student doesn't use it because you have to stop and look at your phone to open it. Typing 4 numbers and ok or a finger pattern is faster for most. Also, phones have their own choices for security. Not everyone has an iPhone or Android or even the same brand of phone. My Ds Google Pixel is very different than my Samsung and both are Android.I'm curious as to how that works?
I am an identical twin. I can't open my sister's phone with my fingerprint, because even identical twins don't have the same fingerprints. (The patterns are formed by how we touch our mother's womb in utero).
We do have the same face, though, but despite being confused for one another all our lives, her phone will not unlock for my face. I presume the technology can discern minute differences more easily than a human can.
IMO it wasn't the killer trying to call the BF, but if it were, I think it would only have worked if he held the girls' fingers and placed them on the phone to unlock. That wouldn't have worked if their fingers were bloody and he'd have had to wipe them off somehow.
Jmo but I am curious as to how you'd use your friend's fingerprint pattern?
I simply don't rule out anything until it is proven otherwise. While it is likely one or both girls made the calls, my own experience tells me that the killer could have been the one making the call, so I don't rule it out until LE has proof otherwise. (My experience: gave the killer an alibi for the supposed time frame, when the time frame was different)
Again, I know nothing of their phones or security on them. I was glad to see the newest reports on the phones showed LE also does not assume it was either or both girls making the calls. That is good police work. I was trying to figure out how they got the timeframe down to a one hour slot between 3-4am.