I was a forensic artist at the FBI for over 18 years (I just retired!) and have worked on many cases of unidentified remains. “Facial approximation” is a method used to attempt to recreate a likeness of a person’s face from the features and shape of their skull. These are really done as a ‘last ditch’ effort to develop leads to a person’s identity after traditional methods like DNA or dental records haven’t provided an identification. Usually, that’s because there isn’t a correlating missing person’s report to connect to the unidentified person. It’s like a puzzle; it only works if all the pieces are there.
In my work, I’ve noticed that a lot of people have unrealistic expectations of what can be predicted from the skull, and what can’t. This is important because we need the public’s help to call in the leads to police and get an identification.
That’s why I decided to tell people how it’s done!
For instance, we know if the eyes are close together, or far apart. We can tell if the person had a long thin nose or a short upturned one. But we often don’t know the hair color or eye color, and most times there’s no way to know how much the person weighed. So, that’s where the artistry comes in, and why these need to be kept more generic than the flashy sculptures you see on CSI or Bones.
P.S: If you ever handle a real skull, make sure to wear gloves! The reason I’m not wearing them in these photos is because the skulls are replicas.
How do we know if the skull is male or female?
That’s the job of the forensic anthropologist, who determines the ‘big four” in skeletal remains cases: estimated age, sex, ancestry, and stature. All that information goes into a report for the forensic artist to study and refer to when creating a facial approximation from the skull.
Forensic artists shouldn’t “go it alone” when doing this work. There should always be a forensic anthropologist involved in the process, from examining the skull to reviewing the sculpture before it’s released to the public.
If a forensic anthropologist isn’t available for review, and there’s no other way that this person is going to have a shot at being identified, then at the very least the artist should review the work with another qualified forensic artist to get their opinion and advice.
How is the mandible (jaw) attached?
When we attach the mandible to the cranium, we need to leave room for the synovial fluid that normally cushions the joints. I use a little bit of cotton padding and some hot glue to keep it secure.
See how there’s still some space between the teeth in the back? That’s because people don’t walk around with their teeth clenched all the time. At least, I hope you don’t!
How do we know how to sculpt the nose?
We get a clue from something called the “anterior nasal spine.” It’s a small bony projection of your nasal aperture, which supports the flesh and cartilage of your nose. If there’s a straight nasal spine, your nose will be straight too. If it points up, you’re going to have an upturned nose, and of course, a downward tip indicates a downturned nose.
You can feel it between your nostrils, under the fleshy part where it wiggles. Better not do this in public though!
How do we know how to position the eyes?
It’s tempting to think that eyes are centered in the orbit, but they aren’t. Numerous studies using MRI data of living people, as well as studies from dissections on cadavers have cleared up this misconception for good. On average, the eyes sit about 1-2mm up and out from the center, as illustrated here. From the side, the eyes are set about 16mm from the front of the cornea to the most anterior (back part) of the eye orbit. Of course, we are biological creatures, so nothing is going to be exact. But we need to have standard guidelines for forensic artists to use, otherwise, it’s just a guessing game, and any pretense of calling this a merging of art and science goes out the window.
I don’t use colored glass eyes, because most of the time these are skeletal remains, so we don’t have any indication of eye color. Even if we think we know (let’s say that the eyes are still present because the body is decomposed and not skeletal) it’s hard to trust the eye color when the person has been deceased for any length of time. Since there’s no fluid or oxygen flowing, the eyes cloud over and can take on a milky, bluish hue. So, death won’t turn your brown eyes blue, but it might look that way.
That’s why I use neutral colored eyes instead; it doesn’t make viewers assume we know the eye color when we don’t. Just think, if someone is looking for their missing brother or cousin who had green eyes, they may disregard a facial approximation that is shown with brown eyes. Why take a chance of losing the potential for identification?
By the way, I made these eyes using a 1″ wooden ball from the hobby shop, adjusted them with clay (eyes aren’t perfectly spherical) and then made duplicates by casting them.
How do we know where the eyelids go?
When we are sculpting the face of an unknown skull, how do we know where the eyelids go?
The outer corner is attached by the “lateral palpebral ligament” to a little bump inside the eye orbit called the “malar tubercle.” This isn’t evident on every skull, so if we can’t feel it, then we attach it about 10mm below the frontozygomatic suture.
We never put clay on the real skull, only replicas!
Here’s the 3D print in the machine, about halfway through the process. You can see the skull taking shape on the left, and the mandible on the right.
When facial approximation was in its infancy, artists sculpted on the actual skull with heavy oil-based clay. That was then, it was a new and emerging field, but there’s no reason to do that anymore. 3D digital scanners and printers are so cheap now, it’ll barely make a dent on your credit card.
There are other good reasons not to sculpt on the skull: it’s evidence. You wouldn’t pack clay around a gun or any other piece of evidence, would you? Think about how that would go over in court.
Also, once you add clay to the skull, you’ve lost your point of reference and could go off-track. Better to sculpt on the replica, and keep the actual skull nearby in a safe place where you can refer to it, and it can’t get damaged. Or, get your DNA all over it.
Here’s a skull being scanned for 3D printing!
See that red line on the photo of the left? That’s where the laser is picking up 3D data on the skull. On the right is what it looks like on the computer when it’s all pieced together.
Tissue depth markers are attached to the replica skull with hot glue
We use tissue depth data gathered from living subjects!
We use tissue depth information to gauge how much clay (flesh) to put on the sculpture. The thickness accounts for the muscles, fat, and skin for each area.
A lot of times we don’t know how much the person weighed, because the remains are skeletonized by the time they are found. So, we just have to go with more average. But, if there’s clothing found or the person was decomposed, we might know they were heavier or lighter, and then adjust the markers from there.
I designed this chart to make it easier for other forensic artists (and me!) to use when attaching tissue depth markers. The data comes from thousands of measurements from CT scans of living people. This way we know it’s more up to date, and the measurements are much more precise. There are still charts from the 1980’s floating around, but we’ve all gotten a bit more “robust” since then, and the technology for collecting measurements is so much more sophisticated.
Hey, guess how they took those measurements in the 80’s? They stuck pins in cadavers! Can you say “eew”?
Then, final images are released to the press
Image credits: www.nbcbayarea.com
This young woman’s remains were found Dec. 14, 2014, on the side of Highway 9 near Booker Creek Road in Saratoga California. The Santa Clara County Sheriff’s detectives determined the “Jane Doe” was a victim of a homicide.
The Santa Clara County coroner determined she was between the ages of 15 to 24 years old and stood between 4 feet 11 inches to 5 feet three inches tall. Medical examiners believe she died sometime between April 2014 and when her remains were found in December 2014.
Do this young woman look familiar, even a bit, to someone you know but haven’t seen in five or more years? Even though she was found in California, it doesn’t mean that’s where she was from. Don’t take this image literally; it’s the best that could be done with the information available. Remember the eye color is unknown; she had brown hair, but it could have been light or dark, and the style was unknown. Her lips could have been thinner or thicker, there’s no way to know for sure based on the skull.
Are you interested in becoming a forensic artist too?
It’s totally possible, but there are two things you must have: artistic skill, and a willingness to join law enforcement (LE).
There are only about 50 or so full-time forensic art positions in the United States, generally in state or federal agencies. But don’t lose hope, because there are about 300+ “dual-duty” forensic artists, and they do most of the work you see in the news or online.
They work their regular job in LE (as police officers, dispatchers, administrative techs, etc), then do the forensic art assignments as they are needed. The vast majority will be doing composite sketches of suspects to start…that’s sort of ‘getting your foot in the door.’ Then, with more experience and training, they may be able to start doing facial approximations for their agency.
I was working as a concept artist at the Johns Hopkins University Applied Physics Laboratory when I saw the job posting for the FBI. I nearly fainted! It seemed like the coolest job in the universe, and it was. Within a few years, I was doing facial approximations all day, every day, and I loved it.
So, the more you know about how forensic artists create these, the better equipped you will be to recognize a missing person. If you see a sculpture or drawing of a facial approximation, you’ll know what to look for. Maybe you’ll even help break a cold case, and help identify someone!
I hope you found all this interesting, and if you want to know more, check out my Instagram. I’m posting more and more all the time, and if you have a question, I’ll answer in a follow-up post and tag you!