Some trace the history of police suspect sketches to French police officer Alphonse Bertillon (1853 – 1914). In all likelihood, some police officer somewhere was creating suspect sketches long before the 1800’s. Regardless, for hundreds of years law enforcement agencies across the world have used artist sketches to aid in criminal investigations. After a crime has occurred a forensic artist interviews a witness and attempts to elicit the perpetrator’s facial traits and distinguishing characteristics. Some forensic sketch artists use an intuitive "free-hand" method while others use "reference images" to assist a witness in recalling or describing different types of facial traits and characteristics – large nose, deep set eyes, receding hair line, etc. This explanation of the process is horribly superficial, but based upon the interview process; the artist sketches a facial image which law enforcement then uses in an effort to generate investigative leads with the goal of eventually identifying the perpetrator.
After a major crime, we have all seen these sketches in newspapers, on television, and now days on social media sites. Sometimes they are free-hand sketches drawn by extremely talented artists and other times they are computer based composite "mug-shot" type images. And on other occasions they are a combination of both free hand sketching and computer generated facial components.
Just HOW ACCURATE are these suspect sketches?
Even more importantly, how effective are they in eventually helping law enforcement identify the perpetrator?
Are they even worth doing?
Is it possible that they often make it harder for law enforcement to find the real perpetrator?
POLICE SUSPECT SKETCH ACCURACY
Hard statistics are difficult to come by, but some research suggests that facial sketches or composite pictures of suspected criminals are useful less than 20% of the time. Other studies put the percentage even lower – maybe as low as 8%. That means that at least 80% of the time, the time and effort spent creating and circulating these pictures are worthless.
But, in some cases police sketch artist renderings or composite images can be very accurate and have led to the capture of many suspects. They have been attributed to helping capture such notable criminals as The Oklahoma Bomber Timothy McVeigh, Derrick Todd Lee – nicknamed the Baton Rouge Serial Killer, Swedish serial rapist Kurt Niklas Lindgren, and many other lesser known criminals.
There are many excellent police sketch artists around the world but Lois Gibson from Houston Texas is recognized as one of the very best. She is in The Guinness Book of World Records as "The World’s Most Successful Forensic Artist." Her sketches have reportedly helped law enforcement capture over 1,300 criminals.
The accuracy and usefulness of suspect facial renderings, whether free hand sketches or computer composites, is only as good as the information provide by witnesses or victims. Everyone sees things differently and eyewitness accounts can often vary widely and are often inaccurate. Police sketch artists who consistently produce accurate pictures must have good artistic skills but their final product is as much a result of the information elicited during the interview process as it is their artistic skill. The artist needs to have an understanding of human memory so they can help the victim recall distinctive facial characteristics and translate that onto paper.
BOTTOM LINE: Most police suspect sketches are not very accurate. If most are inaccurate, why do police keep doing them?
WHAT IS THE VALUE of a police suspect sketch?
Law enforcement knows that police sketches, composite suspect drawings, or a combination thereof, have limitations and are often inaccurate. They understand that it is a rarity that someone will see the image and immediately recognize the perpetrator. But the real purpose of creating and releasing suspect sketches to the public is not to immediately identify the suspect. The real goal is to generate investigative leads that investigators can pursue. Most suspect sketches are released when investigators have few leads and the case is getting stale. Releasing a suspect image is often a last-ditch effort to trigger public interest and re-energize the case.
Some police suspect sketches bear little resemblance whatsoever to the perpetrator. One was recently described as looking "more like a Sesame Street character with a degenerative illness than a real human." But the perpetrator was apprehended due, at least in part, to the publishing of this grossly inaccurate sketch! Publishing this cartoon looking sketch resulted in heightened public interest in this Texas robbery case and this lead to the capture of the perpetrator. Case solved!
The problem of FALSE LEADS.
Some have argued that generating leads based upon a grossly inaccurate image can produce superfluous leads. These "false" leads can cause investigators to spend valuable time and resources chasing down leads that will never amount to anything. This is true. Investigators must be aware of this likelihood and carefully evaluate and prioritize all leads. But, because suspect images are usually only released when evidence is limited and investigators are nearing a deal end, sorting through hundreds or thousands of erroneous leads – just to maybe get a good lead, is just a part of conducting a thorough investigation. One investigator expressed it candidly when he said, "When your case is going nowhere you put the sketch out there and hope for the best or you just give up and put the case on the cold case shelf."
INCREASING THE EFFECTIVENESS of suspect sketches.
Persons viewing a sketch of a suspect should realize that the sketch is likely not very accurate and should not view it too literally. They should realize that the sketch is a representation of a witness or victim’s perception of how the perpetrator looked. They should view it impressionistically and use their imagination, concentrating on basic facial features and the uniqueness’s in the sketch – big lips, large nose, unusual hair style, pierced ear, protruding teeth, pale complexion, high cheek bones, etc.
Then, if one of these features causes you to pause and say to yourself something like: Hey, those lips kind of look like the guy I see at the park sometimes. Or, the guy who works at the Quickie-Mart near where the crime occurred has an earring like that in his left ear; you should not hesitate to report it to police. Remember, law enforcement usually only releases suspect sketches to the media when they have few leads. By releasing the sketch to the media, they are soliciting ALL leads and investigators are skilled in evaluating and prioritizing all leads.
Sometimes a seemingly unimportant tip leads to the arrest of a perpetrator who otherwise would not likely be apprehended.