Finding genetic criminals

On this day in 1905, a British court found brothers, Alfred and Albert Stratton, guilty of murdering and robbing two shopkeepers, Ann and Thomas Farrow. What makes this case notable is the evidence used to support the conviction. There were no reliable witnesses, there was only Alfred Stratton’s right thumb print left on the Farrow’s cash box.

This case marked the first time fingerprint evidence was used in a capital case. While the emerging technology had been used in cases before the Farrow murders, this was the first big case — a case that elevated fingerprint evidence to the criminal justice big leagues.

A variety of biometric (measuring the body) techniques had been used before the Farrow case, but each had a demonstrable weakness. The most prevalent pre-fingerprint technology was the so-called Bertillon System (Anthropometry) devised by the French police officer and biometric researcher Alphonse Bertillon. Bertillon’s method of identification used a complex set of cranial measurements along with photographs. While the measurement aspect of the Bertillon system fell into disuse after two individuals were found to have identical measurements, the photographs live on today as “mug shots.”

Of course, Bertillon’s methods were methodologically descendant from the work of German scientist, Franz Joseph Gall. Around 1800 Gall developed a method he termed “cranioscopy,” a method to divine personality and developmental traits from the shape of a person’s head. This would later be dubbed “phrenology.”

Gall’s methods would later appear in the work of Cesare Lombroso. Lombroso was an Italian scientist, whose most famous work, “The Criminal Man”, theorized that certain criminals were “atavists” or evolutionary throwbacks.

With the development of science and technology over the last 50 years, other biometrically derived innovations have taken place. Facial recognition software is increasingly commonplace. Unlike Bertillon and his forebears, facial recognition measures thousands of points on a person’s face to distinguish them from other similar-looking individuals.

Just last week a team of researchers led by Belgian researcher, Peter Claes, at the Catholic University of Leuven, published an article entitled “Modeling 3D Facial Shape from DNA” in the journal, PLOS Genetics.

As Claes and his co-authors state, “We show that facial variation with regard to sex, ancestry, and genes can be systematically studied with our methods, allowing us to lay the foundation for predictive modeling of faces.”

In other words, Claes has developed a method for taking a person’s DNA and building a 3D model of their face using only genetic information.

The criminal justice world has already taken great interest. Courts have long-permitted the use of DNA evidence at trial. Heretofore that evidence has been used primarily to confirm or refute the presence of a known individual. What makes this technique different is its ability to provide law enforcement a 3D model of a suspect using only DNA.

As Claes observes, “Such predictive modeling could be forensically useful; for example, DNA left at crime scenes could be tested and faces predicted in order to help to narrow the pool of potential suspects.”

Like all emerging technologies, further work needs to be done before they’re ready for routine use by law enforcement.

Even so, New Scientist ( ) reports that Pennsylvania State University researcher, Mark Shriver, (a member of Claes project) is already working with police to see if the method can help find the perpetrator in two cases of serial rape in Pennsylvania.

While this groundbreaking research may indeed represent a seminal evolution of police science, it’s important to keep all of this in proper context. A century before now, fingerprints were state of the art. A century before that it was phrenology. A century before that it was trial by ordeal. One wonders what it will be a century from now.