Composite drawings in criminal investigations

DEFINITION: Artistic rendering of the facial features of unknown persons, often crime suspects, based on eyewitness information for use in narrowing law-enforcement searches.

SIGNIFICANCE: The ability of law-enforcement officials to solve a crime depends largely on the cooperation and participation of private citizens in the investigatory process. Without eyewitness identification, many offenders remain at large and are never brought to justice for their crimes. Police sketch artists often contribute to investigations by creating composite drawings of the perpetrators of crimes based on descriptions provided by victims or other eyewitnesses. The productions of sketch artists have been instrumental in the capture of many notorious criminals, including the serial killer Ted Bundy and Richard Allen Davis, the kidnapper and murderer of twelve-year-old Polly Klaas.

Forensic artists, also known as police artists or sketch artists, are specially trained professionals whose work assists law-enforcement investigators in the identification, apprehension, and of unknown suspects in unsolved criminal cases. Certified by the Forensic Art Certification Board of the International Association for Identification, forensic artists contribute to the investigatory process primarily through their creation of composite drawings or sketches, called composite imagery.

Forensic artists create composite drawings of unknown suspects on the basis of reports from victims or other witnesses (informants) about the perpetrators of unsolved crimes. From memory, an provides a sketch artist with a description of a suspect, and the artist creates a that emerges as the artist obtains increasingly specific information about the suspect’s facial features. With the exception of the largest police departments in the United States, few American law-enforcement agencies employ full-time sketch artists. Most share the services of police artists with other agencies or hire local professional artists on an ad hoc basis to create composite imagery.

Beginnings of Forensic Art

The field of forensic art has a long history. In the United States, the earliest practitioners were the artists of the Old West who created the posters depicting wanted criminals that were displayed in a wide range of public settings, including in churches, schools, saloons, and post offices. During the late nineteenth century, French criminologist Alphonse Bertillon created the first formal system of criminal identification, which included techniques that became the forerunners of forensic art. Bertillon’s book on anthropometry (the study of the dimensions of the human body), Identification anthropométrique; instructions signalétiques (1893; Signaletic Instructions Including the Theory and Practice of Anthropometrical Identification, 1896), laid the groundwork for the basic procedures of composite drawing that continued to influence practitioners of the art.

During the 1950s, a kit designed to aid in the creation of composite imagery, the Identi-Kit, became a huge commercial success. Use of the Identi-Kit became standard practice among US law-enforcement agencies, especially in cases involving multiple victims or other witnesses. The kit contained a large collection of hand-drawn facial features (hairlines, mouths, cheekbones, eyes, noses, ears, and so on) from which informants could choose in building composite faces. By the 1970s, police sketch artists had replaced the use of the Identi-Kit with composite drawings, which produced richer and less contrived portraits of unknown suspects.

Uses of Composite Imagery

Composite drawings can be used in several ways. In most cases, a composite drawing is created to capture the facial appearance of an unknown so that law-enforcement investigators can begin to narrow the pool of viable suspects and better target their search for the unknown offender. Although composite drawings are usually of faces, forensic artists also sometimes provide useful visual depictions of in criminal cases, such as stolen property or automobiles, or of actions that transpired at crime scenes. All of these kinds of images can be submitted as demonstrative evidence in the trial process.

Composite drawings can be modified to simulate how suspects might appear as they naturally change or age or as they might attempt to alter their appearance by adopting various disguises. For example, a sketch artist can modify the original image of a suspect by adding or subtracting weight or by adding signs of aging. Other image modifications might include the addition of various types of facial hair (mustaches, beards, sideburns) and different types of glasses, hats, or piercings.

Creating the Drawings

Forensic artists can create two-dimensional depictions of suspects by hand or with the aid of computer-imaging software. The success of either technique depends largely on the ability of the informant to describe the suspect accurately and on the talent of the in translating the informant’s description into a precise re-creation of the suspect’s facial features.

Police sketch artists must possess not only artistic ability but also effective interviewing, listening, and intuitive skills. The creation of a composite drawing necessitates close communication between the informant and the sketch artist. To jog the informant’s memory, the artist asks the informant a series of questions covering all aspects of the crime incident, including questions about the length of time the perpetrator was observed, the lighting conditions at the crime scene, the distance between the perpetrator and the informant during the incident, and any obstacles that obstructed the informant’s view of the perpetrator.

Helping the informant return to the in their mind’s eye is a critical first step in the composite-drawing process. A well-executed rendering based on inaccurate information about a suspect’s appearance can be costly to a criminal investigation, wasting police time and resources and allowing an to remain at large to commit subsequent crimes. The sketch artist must take care to elicit precise details from the informant that will enable the creation of a successful drawing.

The process of creating the composite image continues with the sketch artist showing the informant a series of photographs that depict various face shapes as well as various types of eyes, noses, hair, ears, and so on. The informant selects from those choices the characteristics that most closely resemble those of the perpetrator, and the police artist assembles the selected features to create the first draft of the composite. The artist then carefully refines the drawing through several iterations until the informant decides that the artist has achieved a match.

The most common type of composite image is a freehand drawing that represents the artist’s attempt to reproduce the informant’s reports as closely as possible. The drawing’s approximation of the suspect’s actual appearance might be close enough to generate productive leads for police investigation, and it might also be close enough to jog the memories of other possible witnesses among the general public.

Some law-enforcement agencies employ computer-based assemblages of features in creating composite drawings, instead of or in tandem with the renderings of sketch artists. Although such software packages are useful, they do have shortcomings. For example, basic packages are restricted in the variations they can generate in terms of human features, which in reality are virtually limitless in their shapes, sizes, and shades of color. Stocking such programs with greater numbers of features is costly and makes the programs more challenging to operate; in addition, it takes more time to find the correct feature when the pool is large. Even with an abundant stock of features, an image program might lack a particular feature or combination of features that fits a given unknown suspect, especially one with an uncommon profile.

Although the technology to create composite images has advanced, such drawings rely on the memories and perceptions of witnesses. Studies have found that witnesses' memories are often faulty. Furthermore, some experts question whether a completed composite image can influence the memory of the witness, making suspect identification more difficult.

Identifying the Dead

In addition to creating images of suspects for use in criminal investigations, police sketch artists are sometimes called upon to lend their skills to the identification of unknown deceased persons whose faces are unrecognizable because of suicide-related trauma, homicide, or accident, or as a result of decay, decomposition, or skeletonization. In such or approximation, tissue depth markers and special drawing techniques are used to produce three-dimensional images.

A thorough examination of the human skull by a forensic anthropologist can reveal a great deal of information about the deceased, including the unknown person’s gender, approximate age, race, and overall size. A forensic artist can then use existing knowledge about the likely depths of tissue covering various parts of the face to fill in missing areas or to correct facial distortions in front- and profile-angle portraits or models so that the decedent’s re-created face can be used for postmortem identification. In some cases, forensic artists use clay to build three-dimensional faces on casts of the skulls of unidentified deceased persons. Facial reconstruction is usually employed only after other avenues of identifying an individual—such as by matching fingerprints, (deoxyribonucleic acid), or dental records—have failed.

Bibliography

Boylan, Jeanne. Portraits of Guilt: The Woman Who Profiles the Faces of America’s Deadliest Criminals. Pocket Books, 2001.

Clement, John G., and Murray K. Marks. Computer-Graphic Facial Reconstruction. Academic Press, 2005.

Fridell, Ron. Forensic Science. Lerner, 2007.

Gibson, Lois, and Deanie Francis Mills. Faces of Evil: Kidnappers, Murderers, Rapists, and the Forensic Artist Who Puts Them Behind Bars. New Horizon Press, 2005.

Pike, Graham. "Facial Composite Technology and Eyewitness Identification." In The Impact of Technology on the Criminal Justice System: A Psychological Overview. Edited by Emily Pica, et al., Routledge, 2024, doi:10.4324/9781003323112.

Taylor, Karen T. Forensic Art and Illustration. CRC Press, 2001.