DNA Never Lies, and Now a Computer Program Can Use It to Make a Mug Shot

Forget about sketch artists and faulty memory. All this software needs is a single hair.

(Photo: 'PLOS Genetics'/Creative Commons)

Mar 26, 2014· 3 MIN READ
Culture and education editor Liz Dwyer has written about race, parenting, and social justice for several national publications. She was previously education editor at Good.

Unless a home is tricked out with security cameras or police can find clear evidence, if a burglar breaks in, there's no way of knowing whodunit. Even if a victim sees the perpetrator and sits down with a sketch artist, memory can be faulty or biased—just ask the countless black men who've "fit the description."

A group of Penn State University researchers have developed a technological solution that uses the one part of us that never lies: DNA. Led by anthropologist Mark Shriver, the research team has created computer software that generates a 3-D facial model. All it needs is something—a hair, a fingernail, or saliva—with your genetic code.

We learn in middle school science class how genetics determines whether a person has blue or brown eyes, or if someone is going to end up brunette or blond. Shriver's team has taken on the much more complicated task of predicting facial structures, such as the spacing between eyes or nose width.

The research, which was recently published in the journal PLOS Genetics, used images of 592 people "with mixed West African and European ancestry from the United States, Brazil, and Cape Verde," a tiny island country in the Atlantic that was once a slave-trading hub. The computer program they developed mapped more than 7,000 facial data points and is now sophisticated enough to recognize "facial variation with regard to sex, ancestry, and genes." This, the researchers say, lays "the foundation for predictive modeling of faces."

If a thief cuts his hand while busting through a window or tosses a ski mask in the bushes, law enforcement already runs any genetic material found on the scene through the FBI's Combined DNA Index System. The problem is, the perpetrator has to have already committed a crime and had his mouth swabbed for DNA for a name—and a mug shot—to pop up. With this new software, however, an image of someone who has never been swabbed can be generated.

That kind of modeling could be a forensic boon. It also expands the already groundbreaking ways forensic evidence is being used to solve crimes. Law enforcement officials were stumped for 25 years over the identity of Los Angeles' Grim Sleeper serial killer. Although the killer left DNA at every crime scene, because he was not previously nabbed for a crime, police had no way to make a positive identification.

In 2010, LAPD detectives were able to catch the killer when they decided to try the first-ever instance of familial DNA matching, which tested material found at crime scenes, against 1 million samples in the database in hopes of finding the killer's cousin, brother, or uncle. The year before, Lonnie Franklin Jr.'s son had been arrested and had his mouth swabbed, which led police to snag his genetic code from an Orange County pizza place. Investigators were able to match Franklin’s saliva to DNA found on 10 victims.

But with as many as 180 women allegedly raped and murdered by the Grim Sleeper, the kind of software the Penn State researchers are creating could have taken DNA from the first victim and generated a mug shot of a killer. Couple that with facial recognition software, and countless lives could have been saved.

Still, it's not hard to imagine some law enforcement officials and get-tough-on-crime politicians wanting samples of all citizens' DNA in a database just in case you commit a crime. While that would undeniably serve as a deterrent and make catching crooks a snap, it's also an area that's ripe for abuse.

My sister works in law enforcement, and although this kind of software would make her job easier, she pointed out a key problem. Although your DNA doesn't lie, criminals make a living of deception. Crime rings could troll restaurants, swipe your biological fingerprint in much the same way the police retrieved the Grim Sleeper's, and plant it at a crime scene. The next thing you know, this new software generates your mug shot, it's scanned through facial recognition software, and you're in a police station being questioned.

That means this mug shot–generating software is likely to receive pushback from privacy advocates and the American Civil Liberties Union. The ACLU recently lost a lawsuit challenging the kind of DNA swabbing that led to the Grim Sleeper's arrest.

Taking DNA used to be protected by the Fourth Amendment: Unless you were arrested and charged with a crime, police needed a search warrant to get it. Last year the Supreme Court upheld law enforcement's right to collect it from all arrestees. Privacy advocates have argued that just because you're arrested doesn't mean you end up being charged. But unless you go through a cumbersome process to get your DNA removed from its database, the police will keep it forever.

While the Penn State software will still need refining, with DNA quickly becoming the modern version of fingerprints, more debates about individual privacy rights and what will help prevent and solve crime are sure to be on the horizon.