CLOSE
Original image
iStock
job secrets
arrow

15 Secrets of Forensic Artists

Original image
iStock

Despite recent advancements in DNA evidence-gathering and high-tech investigative tools, a simple pencil-on-paper sketch can still have a significant impact on criminal cases. Forensic artists who create such sketches use eyewitness accounts, crime scene evidence, skeletal remains, and more to help illustrate and personify criminals and victims—all of it in the pursuit of bringing perpetrators to justice.

To better understand the details of the job, Mental Floss asked three veteran forensic artists about tricks of the trade, why they’re not actually trying to create an exact likeness, and how a bird’s nest can be one of their best tools. Here’s what we’ve learned.

1. SOME SKETCHES ARE INSPIRED BY SMELLS.

When witnesses sit down with law enforcement to relay their description of a criminal’s appearance, they might believe the only relevant information is what their eyes have seen. But according to Melissa Cooper, a freelance forensic artist based in California, all of their senses matter. “It often helps to ask questions that will trigger memory recall,” she says. “During one case interview, I asked [a witness] what stood out the most. She said, ‘His cologne.’ You’d think, ‘Oh, great, I can’t draw that,’ but scent is a huge enabler for memory. Now I know she can smell him and she’s right back in the scene. It’s a perfect state to be in.”

2. THEY NEED TO SUPPRESS THEIR CREATIVITY.

It's easy to imagine that forensic artists might remain hunched over a sketch for hours, trying to insert every last dimple and laugh line they could tease out of a witness. Wrong. According to Cooper, trying to create an exact likeness might make a sketch less likely to resonate with the public. “With a highly realistic portrait, someone might see it who knows the person, but if there’s one thing wrong, one detail, they’ll say, ‘Oh, that’s not my buddy,’” Cooper says. “When it’s more sketchy, more scribbled, you’re leaving more open to interpretation.”

Lisa Bailey, author of Ask a Forensic Artist and a consultant for several law enforcement agencies, agrees. “[Artists] are by necessity keeping their own self-expression and artistry out of it, and not adding information that would create a 'prettier’ image that could lead someone away from recognition.”

3. A SKULL CAN TELL ALL.

500470-LisaBailey.jpg

Courtesy of Lisa Bailey

Forensic artists have responsibilities that go far beyond sketching criminal suspects. Sometimes, they’re called upon to recreate the facial features of a deceased person by “building” out a face using a 3-D replica of a retrieved skull. Teaming with a forensic anthropologist who can usually determine the age, sex, ancestry, and height of the deceased, the artist uses clay to sculpt their missing features. “The skull says so much,” Cooper says. “It can tell you where the eyes angled, where the nostrils went [see image above], where the eyebrows were. Given the choice of a photo of a corpse that’s decomposing or a skull, I’d take the skull.”

4. THERE ARE NOT A LOT OF THEM WORKING FULL-TIME.

By some estimates, there are less than 100 full-time forensic artists in the country. That’s because most of the artists working cases are either freelancers hired by departments or active-duty officers or other agency employees who are called in when needed. “For the average-sized or smaller agency, it doesn't always make sense to have a full-time artist,” Bailey says. “Lots of cases don't require one—there's a video of the suspect, or investigators have already developed leads to the identity of the suspect. Even if an agency estimated the need for 20 or so sketches year, that's still not enough work to justify keeping a full-time artist on the payroll.”

5. DETECTIVES AREN’T ALWAYS HAPPY ABOUT USING SKETCHES.

Charles Jackson, one of the "dual duty" artists who retired from law enforcement as a detective in 2013 but continues to provide forensic sketches, says that his fellow investigators were often reluctant to circulate the art he produced. “The most surprising thing about the job is that it’s hard to get detectives to use the tool,” he says. “Generating evidence based on memory, I think they can sometimes be afraid to [have victims] testify to it.” Despite the potential for defense attorneys to call sketches into question, Jackson says that almost all detectives who wind up using them are glad they did. "It's always been a positive."

6. WITNESSES SIGN SKETCHES.

Once a sketch has been completed and passed on to the investigating officers, it’s considered official police evidence that needs to adhere to a chain of command. To make sure the illustration came from the memory of a specific person, the witness is usually asked to endorse it with a signature. “For a pencil composite, the witness will usually sign the back of the sketch, behind the area of the face so that it won't unintentionally be made public when it's scanned, or can't be accidentally cut off if the sketch is trimmed down to fit in a case file,” Bailey says. The original is then kept on file in an evidence room.

7. BIRD NESTS CAN BE A BIG HELP.

For cases where artists are called to help reconstruct the likeness of a decomposed or otherwise de-featured body, Cooper says that a good reference source for bodies found in the woods can often be found in a very unlikely place. “When dealing with a decomposed body, we’d like to get the color of the hair, and a good place to find that is in a bird’s nest nearby,” she says. “Birds love hair.”

8. SOMETIMES THEIR WORK IS GIVEN AS A GIFT.

Because many forensic artists can be skilled in age progression—trying to realize how a missing child might look years after their disappearance—families with missing loved ones will sometimes inquire about having a sketch done as part of their grieving process. “Sometimes it’s the actual parents, and sometimes it’s just one spouse who wants to give it to the other one,” Cooper says. “I sometimes get scared, not knowing how they’ll react, but they’re usually very grateful.”

9. THEY MIGHT BE DRAWING SOMEONE POLICE ALREADY KNOW ABOUT.

coopersecond.jpg

Courtesy of Melissa Cooper

According to Jackson, not all sketches are done in the proverbial dark. In some instances, authorities have a suspect in mind and are curious if a witness can match that image with their own description. “Detectives frequently call us to corroborate a suspect they have in mind, so it’s basically a composite sketch for a lead,” Jackson says.

10. SOME RECONSTRUCTIONS MIGHT GET A SMILE.

When Bailey is tasked with sculpting the features of a cold case victim, she pays attention to anything unusual or unique about their teeth. If a tooth is crooked or their smile is distinctive, she may decide to add a little smirk. “If there's anything unusual about the teeth, like gaps or crookedness, then we'll sculpt it with parted lips, or with a small smile, because someone might recognize the person just because of the teeth.”

11. SOFTWARE HELPS SOFTEN IMAGES.

IQBiometrix.jpg

IQBiometrix

Some departments without the resources to hire forensic artists rely on software that can digitally render faces. While their efficacy compared to hand-drawn images is open to debate, many forensic artists often rely on software when it’s time to prepare a victim's photographed image for public consumption. “There's a lot of work to do to make an image suitable for public release,” Bailey says. “The artist will have to digitally open the eyes, close the mouth and adjust the jaw, remove swathing and cloth that has been placed around the head, and realign the head so the shoulders aren't hunched up around the ears when they are lying on the morgue table.” Bruises, blood, wounds, and other marks are also retouched.

12. THEY CAN WORK FROM SURVEILLANCE FOOTAGE.

Not all renderings of suspected criminals come from memory. Sometimes, an artist will be called on to fill in the blanks left by incomplete or obscured surveillance footage. “If they have only a three-quarters shot of someone’s head from above, I can look at that,” Cooper says. “Knowing the anatomy of the head, I can show them what the rest of the person would look like.”

13. EARS CAN GIVE THEM A LITTLE TROUBLE.

Jackson says that many witnesses tend to retain visual information relating to the center of the face: the eyes, nose, mouth, and chin. “People generally have a hard time picking out ears,” he says, mainly because they just didn’t notice them. To assist witnesses with feature identification, some artists use an FBI manual that catalogs many common features and asks interviewees to point out which ones look familiar. Jackson uses one; Cooper doesn’t. “Pictures can be suggestible,” she says. “I like [details] to come from them.”

14. THEY WILL NOT DRAW YOU A CHUPACABRA.

Forensic artists occasionally tackle work outside of law enforcement duties: Cooper has worked with the Natural History Museum of Los Angeles with taxidermy efforts for exhibits. But requests to do anything too far off the beaten path are usually met with refusal. “My primary clients are law enforcement, but I once had someone from the Ellen Show wanting me to do a composite of a chupacabra, which Ellen’s wife apparently saw outside their house,” she says. “Someone else wanted to help interpret a dream for them. There’s an element of integrity to the job. I declined. You get a lot of weird requests.”

15. LUCK PLAYS A BIG PART.

Cooper.jpg

Courtesy of Melissa Cooper

Artists working with law enforcement do everything they can to try and take a person’s memories and make them into a tangible image on a page. But no matter how striking the image, nothing will happen unless it ends up in the right place. “We're dealing with luck and timing,” Bailey says. “The right person needs to be looking at the right time. The best, most accurate facial approximation in the world can't do its job if a family member or friend isn't looking.”

Original image
iStock // Ekaterina Minaeva
technology
arrow
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
Original image
iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

Original image
iStock
Sponsor Content: BarkBox
arrow
8 Common Dog Behaviors, Decoded
May 25, 2017
Original image
iStock

Dogs are a lot more complicated than we give them credit for. As a result, sometimes things get lost in translation. We’ve yet to invent a dog-to-English translator, but there are certain behaviors you can learn to read in order to better understand what your dog is trying to tell you. The more tuned-in you are to your dog’s emotions, the better you’ll be able to respond—whether that means giving her some space or welcoming a wet, slobbery kiss. 

1. What you’ll see: Your dog is standing with his legs and body relaxed and tail low. His ears are up, but not pointed forward. His mouth is slightly open, he’s panting lightly, and his tongue is loose. His eyes? Soft or maybe slightly squinty from getting his smile on.

What it means: “Hey there, friend!” Your pup is in a calm, relaxed state. He’s open to mingling, which means you can feel comfortable letting friends say hi.

2. What you’ll see: Your dog is standing with her body leaning forward. Her ears are erect and angled forward—or have at least perked up if they’re floppy—and her mouth is closed. Her tail might be sticking out horizontally or sticking straight up and wagging slightly.

What it means: “Hark! Who goes there?!” Something caught your pup’s attention and now she’s on high alert, trying to discern whether or not the person, animal, or situation is a threat. She’ll likely stay on guard until she feels safe or becomes distracted.

3. What you’ll see: Your dog is standing, leaning slightly forward. His body and legs are tense, and his hackles—those hairs along his back and neck—are raised. His tail is stiff and twitching, not swooping playfully. His mouth is open, teeth are exposed, and he may be snarling, snapping, or barking excessively.

What it means: “Don’t mess with me!” This dog is asserting his social dominance and letting others know that he might attack if they don’t defer accordingly. A dog in this stance could be either offensively aggressive or defensively aggressive. If you encounter a dog in this state, play it safe and back away slowly without making eye contact.

4. What you’ll see: As another dog approaches, your dog lies down on his back with his tail tucked in between his legs. His paws are tucked in too, his ears are flat, and he isn’t making direct eye contact with the other dog standing over him.

What it means: “I come in peace!” Your pooch is displaying signs of submission to a more dominant dog, conveying total surrender to avoid physical confrontation. Other, less obvious, signs of submission include ears that are flattened back against the head, an avoidance of eye contact, a tongue flick, and bared teeth. Yup—a dog might bare his teeth while still being submissive, but they’ll likely be clenched together, the lips opened horizontally rather than curled up to show the front canines. A submissive dog will also slink backward or inward rather than forward, which would indicate more aggressive behavior.

5. What you’ll see: Your dog is crouching with her back hunched, tail tucked, and the corner of her mouth pulled back with lips slightly curled. Her shoulders, or hackles, are raised and her ears are flattened. She’s avoiding eye contact.

What it means: “I’m scared, but will fight you if I have to.” This dog’s fight or flight instincts have been activated. It’s best to keep your distance from a dog in this emotional state because she could attack if she feels cornered.

6. What you’ll see: You’re staring at your dog, holding eye contact. Your dog looks away from you, tentatively looks back, then looks away again. After some time, he licks his chops and yawns.

What it means: “I don’t know what’s going on and it’s weirding me out.” Your dog doesn’t know what to make of the situation, but rather than nipping or barking, he’ll stick to behaviors he knows are OK, like yawning, licking his chops, or shaking as if he’s wet. You’ll want to intervene by removing whatever it is causing him discomfort—such as an overly grabby child—and giving him some space to relax.

7. What you’ll see: Your dog has her front paws bent and lowered onto the ground with her rear in the air. Her body is relaxed, loose, and wiggly, and her tail is up and wagging from side to side. She might also let out a high-pitched or impatient bark.

What it means: “What’s the hold up? Let’s play!” This classic stance, known to dog trainers and behaviorists as “the play bow,” is a sign she’s ready to let the good times roll. Get ready for a round of fetch or tug of war, or for a good long outing at the dog park.

8. What you’ll see: You’ve just gotten home from work and your dog rushes over. He can’t stop wiggling his backside, and he may even lower himself into a giant stretch, like he’s doing yoga.

What it means: “OhmygoshImsohappytoseeyou I love you so much you’re my best friend foreverandeverandever!!!!” This one’s easy: Your pup is overjoyed his BFF is back. That big stretch is something dogs don’t pull out for just anyone; they save that for the people they truly love. Show him you feel the same way with a good belly rub and a handful of his favorite treats.

The best way to say “I love you” in dog? A monthly subscription to BarkBox. Your favorite pup will get a package filled with treats, toys, and other good stuff (and in return, you’ll probably get lots of sloppy kisses). Visit BarkBox to learn more.

SECTIONS
BIG QUESTIONS
BIG QUESTIONS
WEATHER WATCH
BE THE CHANGE
JOB SECRETS
QUIZZES
WORLD WAR 1
SMART SHOPPING
STONES, BONES, & WRECKS
#TBT
THE PRESIDENTS
WORDS
RETROBITUARIES