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 performanc

Varieties of biometric facial techniques for detecting offenders

Many crimes are committed where the only record of the event is in the memory of a witness or victim. Recovering a recognisable image of the offender’s face is then crucial for solving the crime. Traditionally, eyewitnesses describe the offender’s face and select individual facial features – eyes, hair, nose, etc. – to build a ‘composite’. This image is then published in the media so that someone can recognise it and phone the police with a name. Unfortunately, when tested using life-like procedures, this method rarely produces recognisable images. The current paper describes these systems for extracting such biometric information from witnesses. It also describes how useful they are and explores three such approaches for improving their effectiveness. Included are a new method to interview witnesses (a holistic-cognitive interview), a new method to present images to the public (animated composite) and a new system to construct the face (EvoFIT)

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

Evaluation of facial composites utilizing the EvoFIT software program

Facial composites are traditionally created with the assistance of a sketch artist, and the resulting image is then circulated in the police force as well as the public community. However, with the advance of computer technologies and a better understanding of how facial composites are created, composite software systems have developed greatly. EvoFIT, an abbreviation for Evolutionary Facial Imaging Technique, is a computer program used to create composites based on the Darwinian concept. It allows a witness to select for global features of the face, that will in turn be combined together to create new faces that have a greater likeness to the offender. The EvoFIT program aims to boost the low recognition values of facial composite methods currently used. The purpose of this study is to evaluate production of two composites from the same person as a mechanism for improving performance. The use of a second composite, paired composites, and morphed composites is examined as mechanisms for boosting recognition. Ten sets of composites representing ten different volunteers (targets) were created using EvoFIT. The first composite in each set was named correctly 8.3% of the time, the second composites at 18.3%, the paired composites at 20%, and the morphed composites at 23.33%. The results support the theory that use of a second composite, a pair of composites, and morphed composites increases the number of instances in which namers correctly identify the target. This research suggests that it is valuable for a witness to construct a second composite using EvoFIT or similar software

Vision-based landing of a simulated unmanned aerial vehicle with fast reinforcement learning

Landing is one of the difficult challenges for an unmanned aerial vehicle (UAV). In this paper, we propose a vision-based landing approach for an autonomous UAV using reinforcement learning (RL). The autonomous UAV learns the landing skill from scratch by interacting with the environment. The reinforcement learning algorithm explored and extended in this study is Least-Squares Policy Iteration (LSPI) to gain a fast learning process and a smooth landing trajectory. The proposed approach has been tested with a simulated quadrocopter in an extended version of the USARSim Unified System for Automation and Robot Simulation) environment. Results showed that LSPI learned the landing skill very quickly, requiring less than 142 trials

Holistic facial composite construction and subsequent lineup identification accuracy: Comparing adults and children

When the police have no suspect, they may ask an eyewitness to construct a facial composite of that suspect from memory. Faces are primarily processed holistically, and recently developed computerised holistic facial composite systems (e.g., EFIT-V) have been designed to match these processes. The reported research compared children aged 6–11 years with adults on their ability to construct a recognisable EFIT-V composite. Adult constructor’s EFIT-Vs received significantly higher composite-suspect likeness ratings from assessors than children’s, although there were some notable exceptions. In comparison to adults, the child constructors also overestimated the composite-suspect likeness of their own EFIT-Vs. In a second phase, there were no differences between adult controls and constructors in correct identification rates from video lineups. However, correct suspect identification rates by child constructors were lower than those of child controls, suggesting that a child’s memory for the suspect can be adversely influenced by composite construction. Nevertheless, all child constructors coped with the demands of the EFIT-V system, and the implications for research, theory and the criminal justice system practice are discussed

An evaluation of post-production facial composite enhancement techniques

Purpose: This article describes four experiments evaluating post-production enhancement techniques with facial composites mainly created using the EFIT-V holistic system. Design/methodology/approach: Each experiment was conducted in two stages. In Stage 1, constructors created between one and four individual composites of unfamiliar targets. These were merged to create morphs, and in Experiment 3, composites were also vertically stretched. In Stage 2, participants familiar with the targets named or provided target-similarity ratings to the images. Findings: 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). Practical implications: The likelihood of a facial composite being recognised can be improved by morphing and vertical stretch. Originality/value: A greater understanding of the theoretical underpinnings and applied advantage of post-production facial composite techniques should ensure greater acceptance by the criminal justice system, leading to better detection outcomes

The impact of physical and mental reinstatement of context on the identifiability of facial composites

Numerous studies demonstrate that memory recall is improved by reflecting upon, or revisiting, the environment in which information to-be-recalled was encoded. The current thesis sought to apply these ‘context reinstatement’ (CR) techniques in an attempt to improve the effectiveness of facial composites—likenesses of perpetrators constructed by witnesses and victims of crime. Participant-constructors were shown an unfamiliar target face in an unfamiliar environment (e.g., an unknown café). The following day, participants either revisited the environment (physical context reinstatement) or recalled the environmental context in detail along with their psychological state at the time (mental context reinstatement, Detailed CR); they then freely recalled the face and constructed a facial composite using a holistic (EvoFIT) or a feature system (PRO-fit). Over the course of five experiments and meta-analyses, Detailed CR of the environmental context was effective at increasing correct naming and likeness ratings of ensuing composites. The size of the advantage for Detailed CR was dependent on the extent to which the environment had been encoded: the advantage was (i) variable for incidental encoding (Experiments 1-3) with an overall small effect size (ES) (assessed by meta-analysis), (ii) best (very large ES) under intentional encoding (Experiment 3) and (iii) intermediate (large ES) for incidental encoding when participants were encouraged to engage naturally with the environment (Experiment 4). Detailed CR was also found to be effective when combined with a specific interviewing technique (Holistic-Cognitive Interview) where constructors focused on the target’s character; it was no more effective when constructors were prompted to recall the environment in greater detail. Further analyses (Meta-analyses) and additional data (Experiment 5) indicate that the advantage of Detailed CR was mediated by an increase in constructor’s total face recall. Results are interpreted in terms of the encoding specificity principle and can be applied by forensic practitioners who use feature and recognition systems.. This thesis is the first to reveal that context cues can be implemented effectively during forensic face construction using modern composite systems

Eugene: a generic interactive genetic algorithm controller

This paper outlines the development of an open source generic hardware-based interactive Genetic Algorithm controller (Eugene) and explores contexts in which it may be deployed. The system was first applied to the generation of synthetic sound using MIDI and a simple analogue synthesiser with 27 continuous controller values. It was then applied in the area of image evaluation using an image enhancer program with 7 continuous controller values. The system was evaluated by experimental observation of users attempting various tasks with different success criteria. This led to the identification of issues, some of which were specific to, and others divorced from the application domain. These are discussed together with areas for improvement

Holistic facial composite creation and subsequent video line-up eyewitness identification paradigm

The paradigm detailed in this manuscript describes an applied experimental method based on real police investigations during which an eyewitness or victim to a crime may create from memory a holistic facial composite of the culprit with the assistance of a police operator. The aim is that the composite is recognized by someone who believes that they know the culprit. For this paradigm, participants view a culprit actor on video and following a delay, participant-witnesses construct a holistic system facial composite. Controls do not construct a composite. From a series of arrays of computer-generated, but realistic faces, the holistic system construction method primarily requires participant-witnesses to select the facial images most closely meeting their memory of the culprit. Variation between faces in successive arrays is reduced until ideally the final image possesses a close likeness to the culprit. Participant-witness directed tools can also alter facial features, configurations between features and holistic properties (e.g., age, distinctiveness, skin tone), all within a whole face context. The procedure is designed to closely match the holistic manner by which humans’ process faces. On completion, based on their memory of the culprit, ratings of composite-culprit similarity are collected from the participant-witnesses. Similar ratings are collected from culprit-acquaintance assessors, as a marker of composite recognition likelihood. Following a further delay, all participants — including the controls — attempt to identify the culprit in either a culprit-present or culprit-absent video line-up, to replicate circumstances in which the police have located the correct culprit, or an innocent suspect. Data of control and participant-witness line-up outcomes are presented, demonstrating the positive influence of holistic composite construction on identification accuracy. Correlational analyses are conducted to measure the relationship between assessor and participant-witness composite-culprit similarity ratings, delay, identification accuracy, and confidence to examine which factors influence video line-up outcomes