Witness Interviews: Does recall of relational information improve identifiability of a facial composite?

Facial composites are used by Police to generate lines of enquiry; unfortunately composites made by traditional ‘feature’ systems are not often accurately named. One reason could be that these systems tend to rely on descriptions of the criminal’s facial features, when it has been shown that relationships and distances between facial features—the relational information—is of importance for face recognition. Here, we present two experiments to investigate the usefulness of probing for relational information within witness interviews. Participant-witnesses underwent a typical cognitive interview (CI), an interview in which featural information was probed for before relational information (FR), or an interview in which probing for relational information preceded probing for featural detail (RF). Composites constructed of familiar targets with no delay were recognised better in the former two interviews than the latter, suggesting that relational information interferes with subsequent recall of featural information. However, after a 24 hour delay composites constructed of unfamiliar targets did not differ significantly for naming rates by interview type. This indicates no naming benefit for recalling relational information. However, RF composites were rated as significantly better likenesses to target images after a 24-hour delay, and so future work could explore this further to assess what aspect of the image is improved by recall of relational information

The benefit of context for facial composite construction.

Purpose - The aim of this study was to investigate whether the presence of a whole-face context during facial composite production facilitates construction of facial composite images.Design/Methodology - In Experiment 1, constructors viewed a celebrity face and then developed a facial composite using PRO-fit in one of two conditions: either the full-face was visible while facial features were selected, or only the feature currently being selected was visible. The composites were named by different participants. We 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.Findings - In both studies we found that presence of the facial context promoted more identifiable facial composite images.Research limitations/implications – Though this study uses current software in an unconventional way, this was necessary to avoid error arising from between-system differences.Practical implications - Results confirm that composite software should have the whole-face context visible to witnesses throughout construction. Though 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. Originality/value - 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

Familiarity effects in the construction of facial composite images using modern software systems.

We investigate the effect of target familiarity on the construction of facial composites, as used by law-enforcement to locate criminal suspects. Two popular software construction methods were investigated. Participants were shown a target face that was either familiar or unfamiliar to them and constructed a composite of it from memory using a typical ‘feature’ system, involving selection of individual facial-features, or one of the newer ‘holistic’ types, involving repeated selection and breeding from arrays of whole faces. The study found that composites constructed of a familiar face were named more successfully than composites of an unfamiliar face; also, naming of composites of internal and external features were equivalent for unfamiliar targets, but internal features were better named than external features for familiar targets. These findings applied to both systems, although benefit emerged for the holistic type due to more accurate construction of internal features and evidence for a whole-face advantage

Constructing identifiable composite faces: The importance of cognitive alignment of interview and construction procedure.

We investigated the impact of congruency between the witness interview and method used to construct a composite face. Experiment 1, using a typical feature-by-feature composite method, revealed that aligning cognitive processes during interview and face construction enhanced the effectiveness of composites compared with composites produced following unaligned (incongruent) procedures. Experiment 2 revealed that incorporating character judgements in the witness interview substantially enhanced identification of feature-based composites when constructing the central (internal) features first, suggesting that such judgements focus attention on this region of the face. Experiment 3 explored alignment of processes using an approach based on an evolutionary algorithm, a method requiring witnesses to create a composite by selecting from arrays based on the eye-region. A combination of character judgements, first for the whole face and then for the eye region, led to best-identified composites. Overall, results indicate that more effective composites are produced when both interview and construction procedures are aligned cognitively. Results are discussed with relevance to the theory of transfer-appropriate processing (Morris, Bransford, & Franks, 1977)

The impact of external facial features on the construction of facial composites

Witnesses may construct a composite face of a perpetrator using a computerised interface. Police practitioners guide witnesses through this unusual process, the goal being to produce an identifiable image. However, any changes a perpetrator makes to their external facial-features may interfere with this process. In Experiment 1, participants constructed a composite using a holistic interface one day after target encoding. Target faces were unaltered, or had altered external-features: (i) changed hair, (ii) external-features removed or (iii) naturally-concealed external-features (hair, ears, face-shape occluded by a hooded top). These manipulations produced composites with more error-prone internal-features: participants’ familiar with a target’s unaltered appearance less often provided a correct name. Experiment 2 applied external-feature alterations to composites of unaltered targets; although whole-face composites contained less error-prone internal-features, identification was impaired. Experiment 3 replicated negative effects of changing target hair on construction and tested a practical solution: selectively concealing hair and eyes improved identification

Recovering faces from memory: the distracting influence of external facial features.

Recognition memory for unfamiliar faces is facilitated when contextual cues (e.g. head pose, background environment, hair and clothing) are consistent between study and test. By contrast, inconsistencies in external features, especially hair, promote errors in unfamiliar face-matching tasks. For the construction of facial composites, as carried out by witnesses and victims of crime, the role of external features (hair, ears and neck) is less clear, although research does suggest their involvement. Here, over three experiments, we investigate the impact of external features for recovering facial memories using a modern, recognition-based composite system, EvoFIT. Participant-constructors inspected an unfamiliar target face and, one day later, repeatedly selected items from arrays of whole faces, with ‘breeding’, to ‘evolve’ a composite with EvoFIT; further participants (evaluators) named the resulting composites. In Experiment 1, the important internal-features (eyes, brows, nose and mouth) were constructed more identifiably when the visual presence of external features was decreased by Gaussian blur during construction: higher blur yielded more identifiable internal-features. In Experiment 2, increasing the visible extent of external features (to match the target’s) in the presented face-arrays also improved internal-features quality, although less so than when external features were masked throughout construction. Experiment 3 demonstrated that masking external-features promoted substantially more identifiable images than using the previous method of blurring external-features. Overall, the research indicates that external features are a distractive rather than a beneficial cue for face construction; the results also provide a much better method to construct composites, one that should dramatically increase identification of offenders

The importance of detailed context reinstatement for the production of identifiable composite faces from memory

Memory is facilitated by reflecting upon, or revisiting, the environment in which information was encoded. We investigated these ‘context reinstatement’ (CR) techniques to improve the effectiveness of facial composites—visual likenesses of a perpetrator’s face constructed by eyewitnesses. Participant-constructors viewed a face and, after a one-day-delay, revisited (Physical CR) or recalled the environmental context (Mental/Detailed CR) before recalling the face and constructing an EvoFIT or a PRO-fit composite. Detailed CR increased correct naming of ensuing composites, but only when participant-constructors suitably encoded the environment. Detailed CR was also effective when combined with another interviewing tech-nique (Holistic-Cognitive Interview), with focus on a target’s character; it was no more effec-tive prompting constructors to engage in greater environmental recall. Analyses indicate that the Detailed CR advantage was mediated by an increase in face recall. Results are applicable by forensic practitioners to aid eyewitness memory, thereby potentially increasing suspect identification and subsequent arrest rate

Understanding the multiframe caricature advantage for recognizing facial composites.

Eyewitnesses often construct a ‘composite’ face of a person they saw commit a crime, a picture that police use to identify suspects. We described a technique (Frowd et al., 2007, Visual Cognition, 15, 1-31) based on facial caricature to facilitate recognition of these images: correct naming substantially improves when composites are seen with progressive positive caricature, where distinctive information is enhanced, and then with progressive negative caricature, the opposite. Over the course of four experiments, the underpinnings of this mechanism are explored. Positive-caricature levels were found to be largely responsible for improving naming of composites, with some benefit from negative-caricature levels. Also, different frame-presentation orders (forward, reverse, random, repeated) facilitated equivalent naming benefit relative to static composites. Overall, the data indicate that composites are usually constructed as negative caricatures

Catching more offenders with EvoFIT facial composites: Lab research and Police field trials.

Often, the only evidence of an offender’s identity comes from the memory of an eyewitness. For over 12 years, we have been developing software called EvoFIT to help eyewitnesses recover their memories of offenders’ faces, to assist police investigations. EvoFIT requires eyewitnesses to repeatedly select from arrays of faces, with ‘breeding’, to ‘evolve’ a face. Recently, police forces have been formally evaluating EvoFIT in criminal cases. The current paper describes four such police audits. It is reported that EvoFIT composites directly led to an arrest in 25.4% of cases overall; the arrest rate was 38.5% for forces that used a newer, less detailed face-recall interview. These results are similar to those found in the laboratory using simulated procedures. Here, we also evaluate the impact of interviewing techniques and outline further work that has improved system performance

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy