Creating a Three-Dimensional Facial Reconstruction
Forensic artists are also in the business of giving faces to the dead. Learning the identity of a deceased victim is as important to crime investigations as learning the identity of the suspect. Some forensic artists, therefore, specialize in reconstructing what people looked like when they were alive.
Identifying bodies is a common challenge faced by police departments. Whenever human remains are discovered, investigators have a lot of pressing questions. Most importantly, they want to know the victim’s name.
According to Karen T. Taylor, one of the leading forensic artists in the United States, it is necessary to give a name to human remains quickly. “You can’t easily commence a death investigation,” she says, “without first knowing the victim’s identity.”13 Not all bodies in need of identification are murder victims. People who die in any kind of accident that caused severe trauma to the body may need to be identified, for example, but whatever the circumstance, police often need an identification in order to determine what happened during the victim’s last moments and to decide whether a crime was committed.
Police are also ethically compelled, out of respect for the victim and the victim’s loved ones, to make an identification. “Law enforcement agencies are regularly presented with challenging cases of unidentified deceased persons,” says Taylor. “It is both their statutory and moral obligation to make every attempt to identify these individuals.”14 Some forensic artists use a mix of artistic talent and scientific knowledge about the structure of the human face to recreate what the person looked like in life.
The Living Dead
The idea that a human skull could be a canvas for a sculpture is not new. Artists and scientists have long been fascinated by the idea of giving long-buried skulls a new face. Archaeologists and historians are interested in uncovering ancient mysteries by identifying Egyptian mummies or in discovering how an ancient Mayan warrior might have looked before weathering thousands of years in the ground. One of the earliest attempts at facial reconstruction was performed in the 1890s by physician Wilhelm His, who asked a sculptor to model a face on the skull of musician Johann Sebastian Bach.
His’s concept of sculpting the face of a dead person is basically the same process that takes place in the studios of modern facial reconstruction artists. The process is called three-dimensional facial reconstruction, because the finished product is a touchable, three-dimensional face, usually made of clay right on the victim’s skull. The artist’s ability to do this task well could be the detective’s only hope for identifying the victim. Pathologist Ian Hill says that sometimes the only method of identification at a police department’s disposal is the “physical identification by a relative or friend, who is using the person’s physical appearance to recognize him or her.”15 Once a relative or friend comes forward claiming to know the victim, police begin making the dental or DNA comparisons they need to scientifically confirm the identity they are seeking. Because this initial claim of identification by loved ones or acquaintances is often what gives police a clue to work from, forensic facial reconstruction can be very valuable for identifying unknown victims.
In May 2003 a hiker was walking his dog in the ski town of Mammoth Lakes, California, when his pet sniffed out a human skull by the side of the trail. Investigators who were called to the scene soon discovered a shallow grave nearby that contained the rest of the body. Enough of the partially buried corpse remained for police to recognize evidence of a probable stab wound.
“From the first I assumed this was a homicide,” says Detective Paul Dostie of the Mammoth Lakes Police Department. “People don’t stab themselves then cover themselves up with dirt.”16 Dostie needed to identify the victim, however, before he could start investigating how the body might have ended up in the woods in the first place. To help with this task, he sought out a forensic artist skilled at facial reconstruction.
In the case of the Mammoth Lakes victim, as in every case like it, the forensic artist was part of an important team tackling the mystery from many different angles. A facial reconstruction artist can contribute one piece of the puzzle by artistically reversing the processes of decomposition and creating a picture that a friend or relative of the victim might recognize—a picture that could bring in an important tip or lead in the case. “Forensic art provides the connection between an unidentified deceased person and the records needed to identify that person,” says Taylor, describing how a reconstruction is just one step in the crime-solving process. “I have often categorized my role as that of ‘middle man.’”17
Digging Up Details
Before they begin to put a face together, reconstruction artists need background details about their victim, especially the person’s gender and age. The size of the victim is important, too, because the facial features of an overweight victim will look very different than the same features drawn on a person who was slender. To gather clues that can guide the reconstruction, a forensic artist often looks at evidence collected from the crime scene or burial site, such as pieces of the victim’s clothing. A tank top and low-rise jeans suggests the victim was young and female while a floral blouse and polyester slacks might suggest an older female. Sometimes clothes still have tags that indicate a person’s size. Clothes, jewelry, and other accessories found at the site where the body was discovered might give the artist an idea about the victim’s personality, too, such as whether the person wore conservative styles or was a flashy dresser. Personality can be a helpful characteristic for the artist when he or she sits down to re-create a lifelike appearance of the victim.
Forensic artists often work with an anthropologist—a scientist who studies human remains—to deduce from the bones details such as the victim’s gender, size, and age. Anthropologists can tell whether a skeleton is male or female, for example, because certain bones are shaped differently depending on gender. The victim’s height is easy to figure out by measuring the lengths of bones. A person’s age can also be determined—if the bones show signs that they were still growing, the person was a child or teen at the time of death. If bones are frail and brittle, they probably belonged to an elderly person. If there are the marks of pregnancy and childbirth on the bones of the hips and pelvis, the person was a mother.
The artist also looks at the skull and figures out the main facial features of the person whose face she is going to bring back to life. “The artist and anthropologist collaborate to construct the facial features of the unknown individual on the basis of the underlying cranial structure,”18 Taylor says. Skulls themselves tell stories about the person they belonged to, and an artist must pay attention to these stories before she attempts to put flesh back onto bone.
A Face from the Grave
Police determined that the woman whose remains they found in Mammoth Lakes had been dead six to nine months. Since it was May, her body had spent a cold and snowy winter in its grave. Weather, burial conditions, and animal activity all affect the rate at which a body decomposes, and the skull that police handed over to the forensic artist was in a state of decay—meaning it still contained flesh. For many forensic artists, handling bodily remains such as these, parts that have not quite decomposed, is one of the most disturbing aspects of the job. “I have to be able not just to see the grisly scene set before me, but to look past it,” forensic artist Lois Gibson says, describing how she copes with the often gory subject matter of the facial reconstruction process. “I can create something beautiful out of something horrific.”19
Because the flesh changes so much in death—it shrinks and splits, it bulges and sags, and its color might change—even bodies that are discovered fairly soon after death may bear little likeness to how they appeared in life. “The easily changeable nature of
physical appearances presents potent challenges to any attempt to use them as a means of identification,” says Hill, “even in ideal circumstances where there has been little or no postmortem degradation.”20 Many reconstruction artists, therefore, prefer to work from scratch. There is rarely enough left of a face to see how the person really looked. Certainly, there will be no twinkle in the eyes, no smile to the lips, none of the lifelike things an artist can give back to the face. Usually, any flesh remaining on the skull is dissolved away in a strong solution of hydrogen peroxide, and the artist is presented with a clean skull to work on.
A trained artist can begin to determine from the shape of the skull the outline of a distinct and unique face. Decisions
A Face–Lift Long Overdue
In 2005 an anthropologist and a medical examiner in New York were asked to create a facial reconstruction based on X-ray images of a human skull. They decided the skull was that of a young man in his late teens, probably from the northern part of Africa.
They were right— the X-ray images were of the 3,300-year-old skull of ancient Egypt’s famous boy king, Tutankhamun. A group of curious scientists had wanted to see whether the U.S.-based team would reach the same conclusions as teams in France and Egypt.
The similarities in the scientists’ findings showed that facial reconstruction, however old the subject and wherever in the world it is performed, is probably right on the money.
about where to begin adding flesh are not merely artistic. They are made using very specific data—measurements of tissue depth, or the thickness of the facial tissue as it would have been in life all over the face.
Adding It All Up
Knowing the subject’s gender, race, and size are crucial to beginning the reconstruction process, because the depth of the tissue at various points on the face tends to be fairly constant for men and for women, depending on their weight and their racial group. The thickness of an African American man’s forehead just over his right eye, for example, is likely to be about the same for all African American men of the same weight. It is likely to be different for Asian or Caucasian men, for women, or for men who are overweight.
Scientists who study facial tissue have come up with a group of tissue depth scales, or lists of measurements of the average
depth of tissue at many specific points on the human skull. There are scales for the faces of men and women of all the major human races and for different body sizes. A forensic artist must choose one of these scales before beginning a facial reconstruction, and the choice is based largely on the research the artist has already done on the victim. When scientific, tissue-depth data are combined with the specific contours of one individual skull, a unique human face will begin to take shape, one that hopefully looks like the person to whom the skull belonged.
“The theory behind facial reconstruction is that in the same way that we all have unique faces, we all have unique skulls,” says Caroline Wilkinson, a forensic artist with the University of Manchester in England. “It is the small variations in the shape, form and proportions of the skull that lead to the significant variation in our faces.”21 With this special combination of the tissue depths that best fit the victim and the unique lines of the facial bones, a forensic artist can begin to put a face back onto the skull in her hands.
Expressions in Clay
Artists who perform three-dimensional facial reconstruction mold a lifelike face with clay, either directly onto the unidentified victim’s skull or onto a precise plastic model of the skull that has been made especially for the facial reconstruction. Using tissue-depth data from the proper scale for the victim’s gender, race, and size, the artist cuts a series of rubber markers to the length of these depth measurements. These markers are then attached at the proper places on the skull, and the artist begins to fill in the spaces between them with clay. As the clay is built up to the proper depth at each marker, cheeks, lips, a nose, and a forehead begin to appear on the skull. These clay features start looking much as the skin probably did while the
Creating a Three-Dimensional Facial Reconstruction
Forensic artists who sculpt a face onto a skull, using clay, follow these basic steps:
1 The skull is mounted onto a table using a short pipe or pole to hold it steady.
2 A tissue-marker scale is chosen, based on the gender, race, and weight of the unidentified person, to help the artist choose the right tissue depths for the different parts of the face.
3 Tissue markers are cut, using the tissue-marker scale.
4 The tissue markers are glued onto the proper places on the skull.
5 Artificial eyes are put into the eye sockets.
6 Clay is spread onto the skull, using the tissue markers as guides.
7 The clay is painted to add eyebrows, lip and cheek color, facial hair, and other details.
8 Hair, clothing, and accessories are added to finish the reconstruction.
owner of the skull was alive. The finished product is a life-sized object that can be viewed from all sides.
Once the clay face is complete, the technical part of the job is done, and the artist turns his or her attention to the final touches that make a clay face look human. Eyebrows and eyelashes are added to frame a pair of artificial eyes. A wig is chosen, based on hair evidence from the victim’s remains or the artist’s best guess about gender, race, and age. Paint is added to bring lifelike color to cheeks and lips. If any personal items were found with the body, such as glasses or a scarf or necktie, these items are added to the sculpture.
As with composite sketches, the forensic artist must know when to call a sculpture complete. It is not a piece of art, but a piece of forensic art, headed not to a museum but to investigators and possibly the media. The artist puts in just enough detail to make the face lifelike, and then the process must end.
“By allowing artistic ego to interfere,” says Taylor, “the artist risks adding incorrect information that may actually detract from the correct information and discourage recognition and identification.”22 Forensic pathologist Martin P. Evison agrees, warning forensic artists against putting too much into their art, specifically, too much of themselves. “There is a well-known tendency,” he says, “to incorporate one’s own facial features into a reconstruction.”23 Like a composite sketch, a facial reconstruction is better left a little vague. The goal is for someone to see something they recognize in the face, not to recognize every single feature.
Often facial reconstructions, like composite sketches, must be done quickly in cases when a crime has just happened and the crime scene is fresh. In fact, when there is no time to wait for a traditional clay reconstruction, a process that usually takes at least a week, detectives may instead order a two-dimensional facial reproduction—one that is drawn, not sculpted.
A Face in Two Dimensions
With the advances in photography technology that have come about since the days of Wilhelm His, it is sometimes just as accurate to draw a facial reconstruction on a flat piece of paper as to sculpt one onto a skull. Sketching the reconstruction can also be more practical, especially when the skull is too fragile for the sculpting process.
“Extremely fragile skulls may not be strong enough to bear the weight of clay for a sculptural reconstruction,” says Vernon J. Geberth, a former lieutenant commander of the New York City Police Department. “In such cases, particularly if the
damage is in the facial area, a two-dimensional approach may be taken.”24
Whichever method is used, drawing or sculpting, the process of applying tissue depth markers to the skull is the same. “Two-dimensional facial reconstruction follows the same preparatory steps by the artist as those for the three-dimensional method,”25 says Geberth, but instead of applying clay to fill in the spaces between tissue-depth markers, the two-dimensional artist takes photographs of the skull, a frontal view and a side (profile) view, and does the reconstruction on these. The artist places both photographs of the skull side by side on a drawing table, then covers them with vellum, a transparent paper. Using the shape of the bone and the tissue markers as a map, the artist begins sketching a face back onto the skull. Drawing the reconstruction this way, instead of sculpting it, can save time, money, and the actual skull itself.
For the same reasons that two-dimensional drawings are sometimes chosen over three-dimensional sculptures, computer-created images may also be chosen. Facial reconstructions are, after all, a mathematical process that requires computing. Betty Pat. Gatliff, an accomplished forensic artist whose many projects include the facial reconstructions of several victims of the 1970s serial killer John Wayne Gacy, says math formulas help artists decide where facial features should go and how large or small they should be drawn.
Gatliff explains how artists use math to decide how wide a nose should be: “We measure across the nasal aperture, which
is the hole where the nose was. That gives us the total width, and we increase it by ten millimeters, which would be five on either side.”26 These measurements fit into another formula for calculating how far the nose should stick out from the face. “We use two measurements,” Gatliff says, “the width and projection, and when you connect it to the bridge, that establishes the nose. That’s the way I’ve done it for thirty-five years, and it works.”27
Other formulas are used to calculate the shape and placement of eyelids, lips, and other features. These details are difficult or impossible to determine from just looking at the skull, but they are very important for successfully creating a lifelike portrait from a skull.
Computers are an ideal tool for precise facial reconstructions. They can perform math calculations instantly, and they also can adapt images with little effort. With the proper software, it is simple to add effects such as weight or age to a face, try out different hairstyles, change eye color, or even give the person a suntan. These are changes that take considerable time to make on a clay or sketch reconstruction. Computers are even able to use medical technology, such as laser scanners and magnetic resonance imaging (MRI), to provide thousands of tissue-depth measurements for a head and face, compared to traditional clay or pencil reconstructions that are made using fewer than three dozen tissue markers.
Evison is a strong believer in the possibilities of computer-generated reconstructions. “Abandoning the traditional landmarks in favor of approximately 10,000 measurements collected from MRI records will represent a significant increase in the precision and accuracy of facial reconstructions,” he says. He predicts that in the years to come, computer images will be “accurate, rapid, repeatable, accessible, and flexible.”28
Just the same, science and technology are only half of the process. The other half is the art of giving human character to an image, and this is something computers cannot do. Evison admits that although computer images do have many
A handheld laser scanner, somewhat similar to the ones store clerks use to reach across the counter and scan big items sitting in your cart, is now being used by some facial reconstruction experts to scan skulls.
When the artist aims the scanner at the skull, a red laser beam moves across the features of the bone and creates the same image, in three dimensions, on a computer screen. The computer program then connects to a special machine that builds an exact copy of the skull out of resin, the material used to make plastic.
The artist goes to lunch, and when he or she returns an hour later, the copy of the skull is ready to be sculpted into a facial reconstruction.
Artists who are squeamish about touching an actual human skull can now sculpt on a plastic copy instead. Investigators who need the skull for other purposes can have it back. Once the victim is identified, family members can sleep better knowing their loved one’s remains were not clumped up with clay. And everyone can rest assured that if the head is fumbled and dropped during reconstruction, it is only a plastic copy.
advantages over reconstruction sculptures and sketches, the computer models “presently lack the sophistication and accuracy of life.”29
A computer may turn out a facial reconstruction that is mathematically perfect, but what the victim’s loved ones may be looking for—and the one detail to which they may respond—could be a twinkle in the eye or a slightly amused turn of the mouth. No computer, at present, can give a picture this very human touch. “So much of what is incorporated into the process is artistic instinct based on experience from drawing thousands of faces,”30 says Taylor. Police depend on this artistic experience to create a face that may strike a chord among people who knew the victim.
A Cold Case Gets Warmer
Gatliff was the artist whose hands brought the Mammoth Lakes murder victim back to life. A week after she received the victim’s skull, her three-dimensional sculpture of the woman’s face was complete. Photographs of this sculpture were shown on news programs in California and Oaxaca, Mexico, where investigators had determined, from biological and chemical analyses of her remains, that the woman was probably born and raised.
“When the police drawing and reconstruction photograph were shown in Oaxaca, a woman said that the Gatliff facial reconstruction looked like her stepdaughter,”31 says Dostie. Thanks to Gatliff’s expert hands, the Mammoth Lakes Police Department was a big step closer to solving the crime. The woman’s killer, however, was still on the loose, and investigators knew that the longer he avoided capture, the harder it would be to find him. After all, suspects age. If many years pass before they are caught, they may become harder and harder to recognize. In cases that drag on for years, forensic artists may be called upon to perform yet another valuable service in an unsolved case: age-progressing a picture.