5 parts of your body that betray your identity

Privacy news
3 mins
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This post was originally published on July 29, 2015. 

Biometrics is a double-edged sword. Sure, fingerprints and facial recognition can make it fun and easy to open doors, sign in to your phone, and tag your friends on Facebook, but is the convenience worth the risk to your privacy? What you may not know is that some biometrics don’t need your permission to work their magic, and the list of body parts that can reveal your identity even across distances is growing.

Here are five you should be aware of!

Your ears

your ears are betraying your identity

Ear identification isn’t new; a private investigator famously used the ears of French imposter Frédéric Bourdin to pin him as an identity thief, a trick inspired in turn by the investigation of James Earl Ray, the man who assassinated Martin Luther King Jr. But that was just human detective work, and machines are quickly learning the ropes: a 2012 review of ear biometrics reveals a wide variety of methods to classify unique features of ears and recognize individual ears from photographs with over 99 percent accuracy.

And earlier this year, Yahoo Labs published a new project called Bodyprint that uses the capacitive touchscreen on a smartphone to scan and identify the unique signature from a user’s ear. This is close-range recognition, but it’s not hard to imagine how the software could be used to identify you if your phone were hacked. Yikes!

Your eyebrows

your eyebrows are betraying your identity

If you saw Minority Report, or our previous post about a new iris-scanning technique, you already know how your eyes can give you away. But did you know your eyebrows can, too? In 2011 researchers at Carnegie Mellon published a technique for distinguishing people based on the “periocular region”, i.e., the area around your eye, most notably the eyebrows. That means an eyebrow scanner could theoretically take over where a face scanner gets confused, like when someone frowns or smiles, or covers up most of their face. Better use extra-large shades if you want to block this technology! Or consider waxing your eyebrows off all together. We hear that’s kinda trendy.

Your voice

your voice is betraying your identity

What would you do if you thought someone was listening in on your phone calls? If you’re a fan of Breaking Bad or Orphan Black, you’d probably get a “burner”, a cheap temporary cell phone not linked to you. But thanks to voice identification technology, you’ll soon have to do more than that.

That’s because software like the Russian Speech Technology Center’s VoiceGrid Nation lets authorities amass huge databases of unique voice signatures and identify them with over 90 percent accuracy. It’s already being used by law enforcement in Mexico to catalog hundreds of thousands of voices and match them to individuals.

That’s a huge boon for government surveillance. You may have been comforted by the idea that the NSA probably doesn’t have enough manpower to listen to all of your phone calls. But with computer-aided voice recognition, all it needs is enough bandwidth.

Your footsteps

your footsteps are betraying your identity

You can hide your face and you can disguise your voice, but not a lot of people would think to disguise the way they walk. A 2011 study out of Japan reports a system that collected the unique walking “signatures” of 104 barefoot volunteers on a touch-sensitive surface, then attempted to identify them within 10 more steps. Out of those 1,040 steps, the system misidentified only 3 of them. That’s an accuracy rate of 99.8 percent!

Another study from Carnegie Mellon the following year reported similar results using just the accelerometer in a smartphone. The phone, tucked away in a pants pocket, measured the vertical bounce and horizontal speed of participants’ gaits and found them to be unique enough to recognize with over 99 percent accuracy. In other words, soon you won’t even have to be touching your phone for it to identify you!

Your fingerprints… from 2 meters away

Fingerprints are old news when it comes to identification; they’re the original biometric. But did you know some scanners can read the pads of your fingers from a distance? A company called Advanced Optical Systems has a device they call AIRPrint that can scan and identify fingerprints from up to two meters away. U.S. military officials claim to be interested in this technology to keep a safe distance between potentially dangerous intruders and their own security personnel, but who knows what the technology could do if it fell into the wrong hands?

Featured images: X posid / Public Domain Pictures.net, MrSegui / Dollar Photo Club, Erni / Dollar Photo Club, Aleš Nowák / Dollar Photo Club, intoo / Dollar Photo Club (images have been modified)

Johnny 5 is the founding editor of the blog and writes about pressing technology issues. From important cat privacy stories to governments and corporations that overstep their boundaries, Johnny covers it all.