Report on Forensic Sciences

We do not know how often false positive reports are made in a range of forensic science disciplines. In the absence of this information it is important to understand the naive beliefs held by potential jurors about forensic science evidence reliability. It is these beliefs that will shape evaluations at trial. This descriptive study adds to our knowledge about naive beliefs by: 1) measuring jury-eligible (lay) perceptions of reliability for the largest range of forensic science disciplines to date, over three waves of data collection between 2011 and 2016 (n = 674); 2) calibrating reliability ratings with false positive report estimates; and 3) comparing lay reliability estimates with those of an opportunity sample of forensic practitioners (n = 53). Overall the data suggest that both jury-eligible participants and practitioners consider forensic evidence highly reliable. When compared to best or plausible estimates of reliability and error in the forensic sciences these views appear to overestimate reliability and underestimate the frequency of false positive errors. This result highlights the importance of collecting and disseminating empirically derived estimates of false positive error rates to ensure that practitioners and potential jurors have a realistic impression of the value of forensic science evidence.

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Intuitive Error Rate Estimates for the Forensic Sciences

SSRN Electronic Journal ◽

10.2139/ssrn.2817443 ◽

2016 ◽

Cited By ~ 2

Author(s):

Jonathan J. Koehler

Keyword(s):

Error Rate ◽

Forensic Sciences

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Application of Innovative TGA/Chemometric Approach for Forensic Purposes: The Estimation of the Time since Death in Contaminated Specimens

Diagnostics ◽

10.3390/diagnostics11010121 ◽

2021 ◽

Vol 11 (1) ◽

pp. 121

Author(s):

Roberta Risoluti ◽

Giuseppina Gullifa ◽

Vittorio Fineschi ◽

Paola Frati ◽

Stefano Materazzi

Keyword(s):

Multidisciplinary Approach ◽

Vitreous Humor ◽

Classification Model ◽

Forensic Sciences ◽

Time Since Death ◽

Time Of Death ◽

Novel Approach ◽

Chemometric Approach ◽

Postmortem Examinations

Chronothanatology has always been a challenge in forensic sciences. Therefore, the importance of a multidisciplinary approach for the characterization of matrices (organs, tissues, or fluids) that respond linearly to the postmortem interval (PMI) is emerging increasingly. The vitreous humor is particularly suitable for studies aimed at assessing time-related modifications because it is topographically isolated and well-protected. In this work, a novel approach based on thermogravimetry and chemometrics was used to estimate the time since death in the vitreous humor and to collect a databank of samples derived from postmortem examinations after medico–legal evaluation. In this study, contaminated and uncontaminated specimens with tissue fragments were included in order to develop a classification model to predict time of death based on partial least squares discriminant analysis (PLS-DA) that was as robust as possible. Results demonstrate the possibility to correctly predict the PMI even in contaminated samples, with an accuracy not lower than 70%. In addition, the correlation coefficient of the measured versus predicted outcomes was found to be 0.9978, confirming the ability of the model to extend its feasibility even to such situations involving contaminated vitreous humor.

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Potential advantages and limitations of using information fusion in media forensics—a discussion on the example of detecting face morphing attacks

EURASIP Journal on Information Security ◽

10.1186/s13635-021-00123-4 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Christian Kraetzer ◽

Andrey Makrushin ◽

Jana Dittmann ◽

Mario Hildebrandt

Keyword(s):

Information Fusion ◽

Classification Accuracy ◽

Negative Impact ◽

Field Application ◽

Attack Detection ◽

Majority Voting ◽

Forensic Sciences ◽

List Type ◽

Media Forensics ◽

Shafer Theory

AbstractInformation fusion, i.e., the combination of expert systems, has a huge potential to improve the accuracy of pattern recognition systems. During the last decades, various application fields started to use different fusion concepts extensively. The forensic sciences are still hesitant if it comes to blindly applying information fusion. Here, a potentially negative impact on the classification accuracy, if wrongly used or parameterized, as well as the increased complexity (and the inherently higher costs for plausibility validation) of fusion is in conflict with the fundamental requirements for forensics.The goals of this paper are to explain the reasons for this reluctance to accept such a potentially very beneficial technique and to illustrate the practical issues arising when applying fusion. For those practical discussions the exemplary application scenario of morphing attack detection (MAD) is selected with the goal to facilitate the understanding between the media forensics community and forensic practitioners.As general contributions, it is illustrated why the naive assumption that fusion would make the detection more reliable can fail in practice, i.e., why fusion behaves in a field application sometimes differently than in the lab. As a result, the constraints and limitations of the application of fusion are discussed and its impact to (media) forensics is reflected upon.As technical contributions, the current state of the art of MAD is expanded by: The introduction of the likelihood-based fusion and an fusion ensemble composition experiment to extend the set of methods (majority voting, sum-rule, and Dempster-Shafer Theory of evidence) used previously The direct comparison of the two evaluation scenarios “MAD in document issuing” and “MAD in identity verification” using a realistic and some less restrictive evaluation setups A thorough analysis and discussion of the detection performance issues and the reasons why fusion in a majority of the test cases discussed here leads to worse classification accuracy than the best individual classifier

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AUSTRALIAN ACADEMY OF FORENSIC SCIENCES: LECTURE BY DR. JULES H. MASSERMAN

The Medical Journal of Australia ◽

10.5694/j.1326-5377.1968.tb83075.x ◽

1968 ◽

Vol 2 (15) ◽

pp. 646-646

Keyword(s):

Forensic Sciences ◽

Australian Academy

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Hyperspectral Imaging for Bloodstain Identification

Sensors ◽

10.3390/s21093045 ◽

2021 ◽

Vol 21 (9) ◽

pp. 3045

Author(s):

Maheen Zulfiqar ◽

Muhammad Ahmad ◽

Ahmed Sohaib ◽

Manuel Mazzara ◽

Salvatore Distefano

Keyword(s):

Hyperspectral Imaging ◽

Dna Analysis ◽

Forensic Sciences ◽

Blood Protein ◽

Chemical Methods ◽

Acrylic Paint ◽

Spectral Bands ◽

Nail Polish ◽

Spatial Dimensions ◽

Non Destructive

Blood is key evidence to reconstruct crime scenes in forensic sciences. Blood identification can help to confirm a suspect, and for that reason, several chemical methods are used to reconstruct the crime scene however, these methods can affect subsequent DNA analysis. Therefore, this study presents a non-destructive method for bloodstain identification using Hyperspectral Imaging (HSI, 397–1000 nm range). The proposed method is based on the visualization of heme-components bands in the 500–700 nm spectral range. For experimental and validation purposes, a total of 225 blood (different donors) and non-blood (protein-based ketchup, rust acrylic paint, red acrylic paint, brown acrylic paint, red nail polish, rust nail polish, fake blood, and red ink) samples (HSI cubes, each cube is of size 1000 × 512 × 224, in which 1000 × 512 are the spatial dimensions and 224 spectral bands) were deposited on three substrates (white cotton fabric, white tile, and PVC wall sheet). The samples are imaged for up to three days to include aging. Savitzky Golay filtering has been used to highlight the subtle bands of all samples, particularly the aged ones. Based on the derivative spectrum, important spectral bands were selected to train five different classifiers (SVM, ANN, KNN, Random Forest, and Decision Tree). The comparative analysis reveals that the proposed method outperformed several state-of-the-art methods.

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