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The purpose of this paper is to assess the impact of seven variables that emerge from forensic research on facial-composite construction and naming using contemporary police systems: EvoFIT, Feature and Sketch.

The paper involves regression- and meta-analyses on composite-naming data from 23 studies that have followed procedures used by police practitioners for forensic face construction. The corpus for analyses contains 6,464 individual naming responses from 1,069 participants in 41 experimental conditions.

The analyses reveal that composites constructed from the holistic EvoFIT system were over four-times more identifiable than composites from “Feature” (E-FIT and PRO-fit) and Sketch systems; Sketch was somewhat more effective than Feature systems. EvoFIT was more effective when internal features were created before rather than after selecting hair and the other (blurred) external features. Adding questions about the global appearance of the face (as part of the holistic-cognitive interview (H-CI)) gives a valuable improvement in naming over the standard face-recall cognitive interview (CI) for all three system types tested. The analysis also confirmed that composites were considerably less effective when constructed from a long (one to two days) compared with a short (0-3.5 hours) retention interval.

Variables were assessed that are of importance to forensic practitioners who construct composites with witnesses and victims of crime.

Using a large corpus of forensically-relevant data, the main result is that EvoFIT using the internal-features method of construction is superior; an H-CI administered prior to face construction is also advantageous (cf. face-recall CI) for EvoFIT as well as for two further contrasting production systems.

Research suggests that memory for unfamiliar faces is pictorial in nature, with recognition negatively affected by changes to image-specific information such as head pose, lighting and facial expression. Further, within-person variation causes some images to resemble a subject more than others. Here, the purpose of this paper is to explore the impact of target-image choice on face construction using a modern evolving type of composite system, EvoFIT.

Participants saw an unfamiliar target identity and then created a single composite of it the following day with EvoFIT by repeatedly selecting from arrays of faces with “breeding”, to “evolve” a face. Targets were images that had been previously categorised as low, medium or high likeness, or a face prototype comprising averaged photographs of the same individual.

Identification of composites of low likeness targets was inferior but increased as a significant linear trend from low to medium to high likeness. Also, identification scores decreased when targets changed by pose and expression, but not by lighting. Similarly, composite identification from prototypes was more accurate than those from low likeness targets, providing some support that image averages generally produce more robust memory traces.

The results emphasise the potential importance of matching a target's pose and expression at face construction; also, for obtaining image-specific information for construction of facial-composite images, a result that would appear to be useful to developers and researchers of composite software.

This current project is the first of its kind to formally explore the potential impact of pictorial properties of a target face on identifiability of faces created from memory. The design followed forensic practices as far as is practicable, to allow good generalisation of results.

The paper provides a detailed description of standard procedures for constructing facial composites. These procedures are relevant to forensic practice and are contained in the technical papers of this special issue; the purpose of this paper is also to provide an expanding reference of procedures for future research on facial composites and facial-composite systems.

A detailed account is given of the interaction between practitioner and witness for producing a facial composite. This account involves an overview of the Cognitive Interview (CI) and the Holistic CI (H-CI) techniques used to obtain a description of the face of an offender (target); the authors then describe how this information is used to produce a composite from five popular face-production systems: Sketch, PRO-fit, Electronic Facial Identification Technique (E-FIT), EvoFIT and EFIT-V. An online annex is also made available to provide procedural information for additional composite systems.

The work is valuable to forensic practitioners and researchers as a reference for interviewing techniques (involving a CI or an H-CI) and using facial-composite systems.

The authors provide an accessible, current guide for how to administer interviewing techniques and how to construct composites from a range of face-production systems.

The police often ask witnesses and victims to construct a facial composite of people they have seen committing a crime. Research has suggested, however, that these images are of poor quality due to memory decay, the face construction method used and the presence of the external facial features (hair, ears, face shape). In the current work, the role of the most important external feature, hair, was explored. Participants were shown an unfamiliar target face and constructed a composite of it 24 hours later using a modern recognition‐based system and one of three types of hair: exact, similar or poor match to the target. Better‐matching hair was found to help participants construct a more identifiable central region of the face (eyes, brows, nose, mouth). The results highlight the importance of accurate hair at the start of the construction session. Implications for police practice are discussed.

The purpose of this paper is to investigate the potential susceptibility of eyewitness memory to the presence of extraneous background speech that comprises a description consistent with, or at odds with, a target face.

A between-participants design was deployed whereby participants viewed an unfamiliar target face in the presence of quiet, or extraneous to-be-ignored speech comprising a verbal description that was either congruent or incongruent with the target face. After a short distractor task, participants were asked to describe the target face and construct a composite of the face using PRO-fit software. Further participants rated the likeness of the composites to the target.

Recall of correct facial descriptors was facilitated by congruent to-be-ignored speech and inhibited by incongruent to-be-ignored speech compared to quiet. Moreover, incorrect facial descriptors were reported more often in the incongruent speech condition compared with the congruent speech and quiet conditions. Composites constructed after exposure to incongruent speech were rated as worse likenesses to the target than those created after exposure to congruent speech and quiet. Whether congruent speech facilitated or impaired composite construction was found to depend on the distinctiveness of the target face.

The results suggest that the nature of to-be-ignored background speech has powerful effects on the accuracy of information verbally reported from having witnessed a face. Incongruent speech appears to disrupt the recognition processes that underpin face construction while congruent speech may have facilitative or detrimental effects on this process, depending on the distinctiveness of the target face.

This is one of the first studies to demonstrate that extraneous speech can produce adverse effects on the recall and recognition of complex visual information: in this case, the appearance of a human face.

The purpose of this paper is to investigate whether the presence of a whole-face context during facial composite production facilitates construction of facial composite images.

In Experiment 1, constructors viewed a celebrity face and then developed a facial composite using PRO-fit software in one of two conditions: either the full-face was visible while facial features were selected, or only the feature currently being selected. The composites were named by different participants. The authors then replicated the study using a more forensically valid procedure: in Experiment 2 non-football fans viewed an image of a premiership footballer and 24 hours later constructed a composite of the face with a trained software operator. The resulting composites were named by football fans.

In both studies, the presence of the facial context promoted more identifiable facial composites.

Current composite software was deployed in a conventional and unconventional way to demonstrate the importance of facial context.

Results confirm that composite software should have the whole-face context visible to witnesses throughout construction. Although some software systems do this, there remain others that present features in isolation and these findings show that these systems are unlikely to be optimal.

This is the first study to demonstrate the importance of a full-face context for the construction of facial composite images. Results are valuable to police forces and developers of composite software.

The purpose of this paper is to describe four experiments evaluating post-production enhancement techniques with facial composites mainly created using the EFIT-V holistic system.

Experiments 1-4 were conducted in two stages. In Stage 1, constructors created between one and four individual composites of unfamiliar targets. These were merged to create morphs. Additionally in Experiment 3, composites were vertically stretched. In Stage 2, participants familiar with the targets named or provided target-similarity ratings to the images.

In Experiments 1-3, correct naming rates were significantly higher to between-witness 4-morphs, within-witness 4-morphs and vertically stretched composites than to individual composites. In Experiment 4, there was a positive relationship between composite-target similarity ratings and between-witness morph-size (2-, 4-, 8-, 16-morphs).

The likelihood of a facial composite being recognised can be improved by morphing and vertical stretch.

This paper improves knowledge of the theoretical underpinnings of these facial composite post-production enhancement techniques. This should encourage acceptance by the criminal justice system, and lead to better detection outcomes.