Terri Krejci, 60, of Huntsville, Alabama, was working as a night shift supervisor at CVS in 2014 when she learned she had breast cancer. She underwent six months of chemotherapy, then surgery. Her medical team warned her she might lose her hair and experience nausea. She had no idea she might lose her fingerprints.
“It was just after my second round of chemotherapy, and I had a Samsung phone with Touch ID, and it kept saying ‘fingerprint not recognized,'” says Krejci, who is now retired. “Then one of the nurses said, ‘Oh yeah, I think we forgot to tell you about this. This is going to happen.’ They said it might be quite a while before I saw those fingerprints again.”
This created a particular problem because Krejci needed her fingerprint to get into the cancer ward. Each time, someone had to let her into the center until they finally gave up and gave her the code. Ten years later, her hands are mostly back to normal, she says, but she still has to reset the fingerprint scan on her phone regularly.
Langenburg, the forensic scientist, says the problems with fingerprints are not going away anytime soon. He predicts that the trend will be to use multiple biometric factors to compensate for potential fingerprint problems – a retinal scan or facial recognition And for example a fingerprint.
He says that for people who know they have trouble with their fingerprints — construction workers, rock climbers — there are ways to make their hands easier to read. Be sure to drink plenty of fluids and use hand sanitizer or hand lotion immediately before scanning. In Minnesota and Wisconsin, professionals tasked with taking fingerprints use “udder balm,” which is typically used on cows because it makes the fingers a little sticky, which helps capture the fingerprints.
Of course, there are some people who want to have their fingerprints obscured – especially criminals. “They often pay large sums of money to have their fingerprints obscured by acid, surgery or whatever,” says Thomas Busey, a professor of psychological and brain sciences at Indiana University who studies the use of fingerprints and the accuracy of fingerprint analysis.
However, Langenburg says these elaborate procedures often have the opposite of the desired effect, creating a more unique mark. He points to American gangster John Dillinger, who cut his fingers and then doused them with acid, which scarred the middle fingers but left all the fingertips, joints and sides recognizable. “As soon as we see these kinds of red flags, we know immediately that this person is trying to hide their identity. This is such nonsense that has been going on for 100 years, and it doesn’t work,” Langenburg says.
Busey finds it odd that we’ve ultimately focused on using fingerprints for biometric identification. Criminals’ fingerprints typically involve all ten fingers, plus the palms of their hands, capturing a huge amount of detail, whereas a phone, computer or airport scanner uses just a single finger, or just a section of that finger. It’s a very limited identifier if something goes wrong – and besides, word gets around.
“You probably have a password for your computer, and you probably don’t get into the habit of sharing your password with other people,” says Busey. “But if your fingerprint is your password, you’re literally leaving your password on every object you touch.”
