A Test of the Passalacqua Age at Death Estimation Method Using the Sacrum

A test of the accuracy of the Passalacqua (J Forensic Sci, 5, 2009, 255) sacrum method in a forensic context was performed on a sample of 153 individuals from the J.C.B. Grant Skeletal Collection. The Passalacqua (J Forensic Sci, 5, 2009, 255) method assesses seven traits of the sacrum using a 7‐digit coding system. An accuracy of 97.3% was achieved using the Passalacqua (J Forensic Sci, 5, 2009, 255) method to estimate adult skeletal age. On average each age estimate differed by 12.87 years from the known age. The method underestimated the age of individuals by an average of 4.3 years. An intra‐observer error of 6.6% suggests that the method can be performed with precision. Correlation and regression analysis found that the sacral traits used in the Passalacqua (J Forensic Sci, 5, 2009, 255) method did not have a strong relationship with age or an ability to strongly predict age. Overall, the method was not practical for use in a forensic context due to the broad age ranges, despite the high accuracy and low intra‐observer error.     

An Improved Version of a Tool Mark Comparison Algorithm

Chumbley et al. (2010) described a statistically based algorithm for comparing pairs of tool marks. They presented empirical evidence that the algorithm produces well‐separated similarity score values for “matching” and “non‐matching” pairs of tool marks. However, the algorithm has two substantial weaknesses. First, it is “uncalibrated” in the sense that error rates can be determined only through empirical investigation. Second, it relies on a randomized test and can lead to different similarity scores when the algorithm is repeatedly applied to the same pair of tool marks. We present an improved version of the procedure, which eliminates the randomized scores and yields more consistent and predictable error rate control. This is accomplished by replacement of a random sampling step from the original algorithm with a deterministic process. We demonstrate the improved algorithm and compare its performance to the original by applying to known “matching” and “non‐matching” pairs of tool marks.     

The Power of Exclusion using Automated Osteometric Sorting: Pair‐Matching,

This study compares the original pair‐matching osteometric sorting model (J Forensic Sci 2003 ;48:717) against two new models providing validation and performance testing across three samples. The samples include the Forensic Data Bank, USS Oklahoma, and the osteometric sorting reference used within the Defense POW/MIA Accounting Agency. A computer science solution to generating dynamic statistical models across a commingled assemblage is presented. The issue of normality is investigated showing the relative robustness against non‐normality and a data transformation to control for normality. A case study is provided showing the relative exclusion power of all three models from an active commingled case within the Defense POW/MIA Accounting Agency. In total, 14,357,220 osteometric t‐tests were conducted. The results indicate that osteometric sorting performs as expected despite reference samples deviating from normality. The two new models outperform the original, and one of those is recommended to supersede the original for future osteometric sorting work.     

A Robust Approach to Automatically Locating Grooves in 3D Bullet Land Scans

Land engraved areas (LEAs) provide evidence to address the same source–different source problem in forensic firearms examination. Collecting 3D images of bullet LEAs requires capturing portions of the neighboring groove engraved areas (GEAs). Analyzing LEA and GEA data separately is imperative to accuracy in automated comparison methods such as the one developed by Hare et al. (Ann Appl Stat 2017;11, 2332). Existing standard statistical modeling techniques often fail to adequately separate LEA and GEA data due to the atypical structure of 3D bullet data. We developed a method for automated removal of GEA data based on robust locally weighted regression (LOESS). This automated method was tested on high-resolution 3D scans of LEAs from two bullet test sets with a total of 622 LEA scans. Our robust LOESS method outperforms a previously proposed “rollapply” method. We conclude that our method is a major improvement upon rollapply, but that further validation needs to be conducted before the method can be applied in a fully automated fashion.     

What is the magnitude of the subpopulation effect?

The effect of population subdivision on estimated match probabilities has been raised [Nature 339 (1989) 501; Am. J. Hum. Genet. 48 (1991) 819; Science 254 (1991) 1921]. Previous work [J. Forensic Sci. 39 (1994) 319; J. Forensic Sci. 39 (1994) 988; Am. J. Hum. Genet. 55 (1994) 533] has compared product rule estimates from differing databases and found that the "subpopulation" error may be of the order of a factor of 10. This approach compares an estimate with an estimate. This paper uses simulation to extend these studies by allowing a comparison to a 'true match probability' and supports the conclusion that subpopulation effects are mild. In addition the performance of recommendations 4.1 and 4.2 of NRC II [National Research Council and C.O.D.F. Science, The Evaluation of Forensic DNA Evidence, National Academy Press, Washington, DC, 1996].     

Use of 2D:4D Digit Ratios to Determine Sex

Second to fourth digit ratios (2D:4D) are sexually dimorphic in human hands and established by the 13th gestational week. Application of 2D:4D for determining sex in living individuals by Kanchan et al. (Forensic Sci Int, 181, 2008, 53.e1) produced classification rates of 80% for males and 74–78% for females. Few studies have explored the use of 2D:4D for sexing skeletal remains. We test estimated finger lengths, phalanx lengths, and 2D:4D derived from hand bones for determining sex. Maximum phalanx length was collected using a mini‐osteometric board from 451 individuals of known age, sex, and ancestry in four skeletal collections. Logistic regression of 2nd and 4th digit finger and phalanx lengths produced classification rates greater than 80%. Digit ratios, however, failed to reach classification rates greater than 59%. Our results support those of Voracek (Forensic Sci Int, 185, 2009, e29) and suggest that 2D:4D may be population‐specific and thus inappropriate for universal application as a means of determining sex.     

Pronasale Position: An Appraisal of Two Recently Proposed Methods for Predicting Nasal Projection in Facial Reconstruction

This study examines two recently proposed methods for predicting nose projection from the skull, those developed by Stephan et al. (Am J Phys Anthropol 122, 2003, 240) and Rynn et al. (Forensic Sci Med Pathol 6, 2010, 20). A sample of 86 lateral head cephalograms of adult subjects from Central Europe was measured, and the actual and predicted dimensions were compared. Regarding nose projection (the anterior and vertical position of the pronasale), in general, the method of Rynn et al. (Forensic Sci Med Pathol 6, 2010, 20) was found to perform better and with less error variance than the method of Stephan et al. (Am J Phys Anthropol 122, 2003, 240), but the mean difference between the actual and predicted values did not exceed 2.2 mm (6.5% of the actual dimension) in most of the variables tested. The vertical dimensions of the nose were predictable with greater accuracy than the horizontal dimensions. Although the mean error of both methods is not great in practice and thus both methods could be considered to be “accurate,” the real variance of error should not be overlooked.     

Repeatability and reproducibility of earprint acquisition

For all forensic disciplines dealing with identification -- e.g., of glass, tool marks, fibers, faces, fingers, handwriting, speakers -- in which manual (subjective, nonautomated) processes play a role, operator dependencies are relevant. With respect to earprint identification, in the period 2002-2005, the Forensic Ear Identification research project collected a database of 1229 donors, three prints per ear, and laid down a "best practice" for print acquisition. Repeatability and reproducibility aspects of the print acquisition are tested. The study suggests that different operators may acquire prints of differing quality, with equal error rates of the matching system ranging from 9% to 19%. Moreover, it turns out that "matching" earprints are more alike when taken in a consecutive row than when taken on separate occasions. This underlines the importance of (1) studying operator effects, (2) operator training, and (3) not gathering "matching" reference material at the same occasion.     

Signature authentication by forensic document examiners.

We report on the first controlled study comparing the abilities of forensic document examiners (FDEs) and laypersons in the area of signature examination. Laypersons and professional FDEs were given the same signature-authentication/simulation-detection task. They compared six known signatures generated by the same person with six unknown signatures. No a priori knowledge of the distribution of genuine and nongenuine signatures in the unknown signature set was available to test-takers. Three different monetary incentive schemes were implemented to motivate the laypersons. We provide two major findings: (i) the data provided by FDEs and by laypersons in our tests were significantly different (namely, the hypothesis that there is no difference between the assessments provided by FDEs and laypersons about genuineness and nongenuineness of signatures was rejected); and (ii) the error rates exhibited by the FDEs were much smaller than those of the laypersons. In addition, we found no statistically significant differences between the data sets obtained from laypersons who received different monetary incentives. The most pronounced differences in error rates appeared when nongenuine signatures were declared authentic (Type I error) and when authentic signatures were declared nongenuine (Type II error). Type I error was made by FDEs in 0.49% of the cases, but laypersons made it in 6.47% of the cases. Type II error was made by FDEs in 7.05% of the cases, but laypersons made it in 26.1% of the cases.     

Withdrawn: Suicide: Exploring the Relationship Between Modality and Population Demographic (San Mateo County,CA, USA 2007–2018): A Population‐Based Study

Withdrawal: Botham AD. Suicide: Exploring the Relationship Between Modality and Population Demographic (San Mateo County, CA, USA 2007–2018): A Population‐Based Study. J Forensic Sci 2019;64(6):1750‐60 ( https://onlinelibrary.wiley.com/doi/10.1111/1556-4029.14090 ) The above article, first published online on June 03, 2019, in Wiley Online Library, has been withdrawn at author’s request, and in agreement between the author, the JFS Editor‐in‐Chief (Dr. Michael Peat), and John Wiley & Sons Ltd. The withdrawal has been agreed to by all parties given the article includes sensitive data which was not authorized for publication.     

Fingerprint error rate on close non‐matches

The accuracy of fingerprint identifications is critically important to the administration of criminal justice. Accuracy is challenging when two prints from different sources have many common features and few dissimilar features. Such print pairs, known as close non‐matches (CNMs), are increasingly likely to arise as ever‐growing databases are searched with greater frequency. In this study, 125 fingerprint agencies completed a mandatory proficiency test that included two pairs of CNMs. The false‐positive error rates on the two CNMs were 15.9% (17 out of 107, 95% C.I.: 9.5%, 24.2%) and 28.1% (27 out of 96, 95% C.I.: 19.4%, 38.2%), respectively. These CNM error rates are (a) inconsistent with the popular notion that fingerprint evidence is nearly infallible, and (b) larger than error rates reported in leading fingerprint studies. We conclude that, when the risk of CNMs is high, the probative value of a reported fingerprint identification may be severely diminished due to an elevated false‐positive error risk. We call for additional CNM research, including a replication and expansion of the present study using a representative selection of CNMs from database searches.     

Age estimation by a dental method: a comparison of Lamendin's and Prince & Ubelaker's technique

Lamendin et al. (J Forensic Sci 1992;37:1373) developed a general technique to estimate age of adults at death using two dental features: periodontosis and translucency of the tooth root. Prince and Ubelaker (J Forensic Sci 2002;47:107) modified this method, creating a formula for each sex and for different ancestries, and obtained more precise age estimations. In the present study, the validity of each method was tested in 45 males and 34 females of Spanish Caucasian origin, and a novel formula, based on Prince and Ubelaker method, was specifically developed for a population of mixed racial origin (mestizo) from Colombia, and findings obtained were again compared with those yielded by Lamendin adult dental aging technique. The Prince and Ubelaker method proved more accurate than the Lamendin technique in the Spanish Caucasian population, and our Prince and Ubelaker-based formula was also more accurate than the Lamendin et al. In both populations, the Lamendin method showed a higher mean error in estimations of the age of youngest and oldest individuals. These findings confirm the need to create specific formulas for each human group in order to obtain more accurate age estimates.     

An Analysis on the Choice of Alpha Level in the Osteometric Pair‐matching of the Os Coxa,Scapula, and Clavicle

This study compares the use of 0.05 and 0.10 alpha levels with the updated osteometric pair‐matching model on two samples of the os coxa, scapula, and clavicle. The samples include the Forensic Data Bank, and the osteometric sorting reference used within the Defense POW/MIA Accounting Agency. Mixed‐effects two‐way analyses of variance were used to analyze bilateral asymmetry in the standard measurements. In total, 3,793,566 t‐tests were conducted for osteometric pair‐matching analysis. The results indicate high levels of exclusion power, and accuracy can be obtained with the os coxa and scapula. The clavicle standard measurements capture too much asymmetry causing a lower exclusion to accuracy ratio for osteometric pair‐matching relative to other elements. Both 0.05 and 0.10 alpha levels provide acceptable levels of performance. A lower alpha level will result in higher accuracy with less exclusion, and a higher alpha level will result in lower accuracy with more exclusions.     

A Comparative Assessment of the Chen et al. and Suchey‐Brooks Pubic Aging Methods on a North American Sample, ,

Accurately estimating the age‐at‐death of adult human skeletons is fundamental in forensic anthropology. This study evaluates the accuracy of two pubic bone age estimation methods—Chen et al. and Suchey‐Brooks. Specimens were obtained from a known collection of modern pubic bones curated at the Maricopa County Forensic Science Center in Phoenix, Arizona. A sample of 296 left male pubic bones of European ancestry was statistically evaluated via bias, absolute mean error, and intra‐ and inter‐observer error. Results indicate that the two methods are similar; the Suchey‐Brooks method is the most accurate for aging young adults (error c. 7 years), while the Revised Chen et al. method is most accurate for aging middle‐age adults (error c. 6 years). Thus, the Chen et al. method is an important contribution to forensic anthropology for aging older adult skeletal remains. There are, however, some limitations such as subjectivity and the intricate scoring system of Chen et al. method.     

Sex Determination from the Second Cervical Vertebra: A Test of Wescott’s Method on a Modern American Sample*

Abstract: Numerous methods for establishing a biological profile exist; however, many of these methods rely on the recovery of several specific bones or on fragile skeletal elements that are sometimes irrecoverable. It is for this reason new methods utilizing other previously under‐documented bones should be established and tested by the forensic anthropological community. This study tests the accuracy of Wescott’s (J Forensic Sci 2000;45(2)) method for determining sex from the second cervical vertebra. Specimens were drawn from the donated skeletal collection curated at the Hamilton County Forensic Center (n = 57) and the William M. Bass Donated Skeletal Collection (n = 243). Both intra‐ and inter‐observer error rates were low and accurate classifications ranged from 78% (females‐Function 1) to 90.6% (males‐Function 5). Of the five functions, Function 4 achieved the highest overall accuracy, with 260 individuals (86.7%) falling into the correct category. Overall, this method is an effective classificatory tool for sex estimation.     

Withdrawn: Hair Analysis for Drug‐Facilitated Crime: The Critical Role of Hair Growth Rate

The following article from the Journal of Forensic Sciences, “Hair Analysis for Drug‐Facilitated Crime: The Critical Role of Hair Growth Rate” by Koren G, Bellaish E, Maman K, published online on 3rd September 2019 (1) on Wiley Online Library has been withdrawn at the authors’ request, and in agreement between the authors, the Journal’s Editorial Office, and John Wiley & Sons, Inc. The withdrawal has been agreed to by all parties due to material included in the article being involved in current litigation. Reference 1. Koren G, Bellaish E, Maman K. Hair analysis for drug‐facilitated crime: the critical role of hair growth rate. J Forensic Sci 2019;54(5):1574–5. https://doi.org/10.1111/1556-4029.14013 .     

Application of automatic image analysis (IBAS system) to age calculation. Efficiency in the analysis of several teeth from a single subject.

In a previous paper (M. López-Nicolás et al., Forensic Sci. Int., 45 (1990) 143-150) we obtained a model of multiple regression to estimate age using computerized image analysis (IBAS) to study teeth. This method should provide more precise measurements of the parameters involved and to test this hypothesis we have carried out a blind study using more than one tooth from the same individual in order to check the diagnostic accuracy of the method. Our results show that individual variability introduced serious errors in tooth age estimation using computerized image analysis. However the study of more than one tooth per individual improves the accuracy of age estimation. Specific cases should therefore be interpreted cautiously, as a degree of variability can be expected using the parameters defined in this method.     

Application of Enhanced Point Estimators to a Sample of In Vivo CT‐derived Facial Soft Tissue Thicknesses

Facial approximations based on facial soft tissue depth measurement tables often utilize the arithmetic mean as a central tendency estimator. Stephan et al. (J Forensic Sci 2013;58:1439) suggest that the shorth and 75‐shormax statistics are better suited to describe the central tendency of non‐normal soft tissue depth data, while also accommodating normal distributions. The shorth, 75‐shormax, arithmetic mean, and other central tendency estimators were evaluated using a CT ‐derived facial soft tissue depth dataset. Differences between arithmetic mean and shorth mean for the tissue depths examined ranged from 0 mm to +2.3 mm (average 0.6 mm). Differences between the arithmetic mean plus one standard deviation (to approximate the same data points covered by the 75‐shormax) and 75‐shormax values ranged from ?0.8 mm to +0.7 mm (average 0.2 mm). The results of this research suggest that few practical differences exist across the central tendency point estimators for the evaluated soft tissue depth dataset.     

A Japanese computer-assisted facial identification system successfully identifies non-Japanese faces

The method developed by Yoshino et al. in [Forensic Sci. Int. 109 (2000) 225 and Jpn. J. Sci. Tech. Iden. 5 (2000) 9] and already being applied in Japan utilizes a three-dimensional (3D) physiognomic rangefinder combined with a computer-assisted superimposition system. Facial outlines can be compared between two-dimensional (2D) surveillance images and data extracted from 3D images obtained from the rangefinder. Also, the loci of potentially concordant features can be compared and differences measured. The method is largely objective and gives statistics for false positive/false negative findings. This recently developed method by Yoshino et al. is currently being introduced to the Japanese courts. To enable courts outside Japan to assess the admissibility of this new method, studies of non-Japanese faces have been undertaken and shown to produce similar low error rates. The present authors, therefore, consider the Yoshino method to be applicable in a non-Japanese context. As part of this study a comparison of morphological features between two ethnic groups has been undertaken using 3D measurements for the first time and will serve as the foundation for an anthropological database in the future.     

Archived or directly swabbed latent fingerprints as a DNA source for STR typing

Former studies [Nature (1997) 387, Electrophoresis 20 (1999) 2870, P. Van Renterghem, D. Leonard, C. De Greef, Progress in Forensic Genetics, Vol. 8, 2000, p. 501, J. Forensic Sci. 45 (3) (2000) 687] have shown that even a single skin contact, documented by a latent fingerprint, can transfer enough DNA for a genetic analysis. It was proven in these studies that it is possible to swab fingerprints from surfaces [Nature (1997) 387, Electrophoresis 20 (1999) 2870, P. Van Renterghem, D. Leonard, C. De Greef, Progress in Forensic Genetics, Vol. 8, 2000, p. 501] and use them as a DNA source. Usually, however, discovered fingerprints are removed with scotch tape and placed on evidence cards for further investigation.In this study, we tried to assess the potential use of latent fingerprints as a DNA source for STR typing. The materials (magnetic powder, soot powder and scotch tape) used for visualization and archiving fingerprints in Germany were tested for their PCR inhibitory characteristics. Then, fingerprints were placed on clean glass surfaces, visualized and tested for their usefulness as a DNA source.Obtained DNA was quantified and tested in an STR system. Partly it proved possible to type fingerprints taken directly from the surface as well as fingerprints removed from the surface with scotch tape.