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JFI Abstracts from 2019

Issue 1: January-March 2019

Letter to the Editor

Author(s): Jim Hoerricks, PhD
Type: Letter to the Editor
Published: 2019, Volume 69, Issue 1, Page 001
Abstract: Re: Lack of Enforcement of Standards as Regards the Testing of Human Subjects

Letter to the Editor

Author(s): Jim Hoerricks, PhD
Type: Letter to the Editor
Published: 2019, Volume 69, Issue 1, Page 005
Abstract: Re: Meline, K. A.; Bruehs, W. E. A Comparison of Reverse Projection and Laser Scanning Photogrammetry. J. For. Ident. 2018, 68 (2), 281292.

Latent Image Transferred from Banknote

Author(s): Aaron Dove
Type: Case Report
Published: 2019, Volume 69, Issue 1, Page 013
Abstract: An unlikely transfer of detail, initially thought to be friction ridges, was found on the inside of a plastic bag after processing the bag with cyanoacrylate fumes. Upon further examination, it was instead determined to be the partial image of Queen Elizabeth II from a Canadian $20 Frontier series polymer banknote.

Artifacts Caused by Livescan Affect a Latent Print Comparison: An Actual Case

Author(s): Andrea Giuliano
Type: Case Report
Published: 2019, Volume 69, Issue 1, Page 020
Abstract: Occasionally, livescan devices produce images with artifacts that could later affect the comparison with a latent print. This issue may arise in court. The case presented in this paper reaffirms that the quality of known prints stored in a database remains a critical subject.

Examining the Effectiveness of Processing Fired Cartridge Cases for Latent Evidence

Author(s): Stacey Johnson
Type: Technical Note
Published: 2019, Volume 69, Issue 1, Page 027
Abstract: It is reasonable to assume that when an individual loads an unfired round into a weapon, latent print evidence and touch DNA evidence may be deposited on the round. One agency that Raleigh/ Wake City-County Bureau of Identification serves had shared information that it felt it had more success with pursuing touch DNA extraction from fired cartridge cases than from processing for latent print evidence. Latent prints were deliberately placed on a sample of unfired rounds. Another sample of unfired rounds was handled naturally prior to being fired. All of the fired cartridge cases were processed with cyanoacrylate and rhodamine 6G dye stain. Minimal ridge detail was observed on the deliberately handled cartridge cases, but the latent detail was determined to be not of value for identification. Latent detail was not observed on any of the naturally handled fired cartridge cases. The conclusion that was reached was that there may be better methods of collecting identifiable evidence from fired cartridge cases, including touch DNA.

Performance Review of the FF-1.0 Forensic Filter and the Expose Curved Barrier Filter by Arrowhead Forensics

Author(s): Elisha D. Sorum
Type: Technical Note
Published: 2019, Volume 69, Issue 1, Page 035
Abstract: The documentation of fluorescent fingerprints is commonly accomplished by emitting a specific wavelength of light via an alternate light source onto the substrate then photographing the results with an orange barrier filter attached to a camera lens and adjusting camera settings for the optimal possible contrast. However, many substrates may f luoresce at similar wavelengths as the latent prints, causing the latent prints to be weak or obscured. Having a choice between the standard orange barrier filter, the new FF-1.0 Forensic Filter, and the new Expose Curved Barrier Filter, or a combination thereof, will allow additional contrast of fluorescent latent prints by blocking the inherent fluorescence in certain substrates that may fluoresce at similar wavelengths as the latent fingerprints.

The Effect of Household Cleaning Agentson Blood and the Suitability for Screening Using the Phenolphthalein Test

Author(s): Masha Signaevsky
Type: Article
Published: 2019, Volume 69, Issue 1, Page 049
Abstract: The phenolphthalein test is used in many forensic laboratories to presumptively reveal the presence of blood on an item of evidence. The mechanism of this test uses phenolphthalin, a chemical indicator, followed by hydrogen peroxide, an oxidizer, to detect the hemoglobin protein. The resulting pink color is attributed to the presence of blood; however, it may also be indicative of a chemical compound that has had an oxidative interaction with the indicator compound. At a bloody crime scene, it is common to expect an attempted clean-up using various cleaning agents, many of which have oxidizing capability. For this experiment, 40 cleaning products were tested with fresh blood on sterile swabs and on filter paper to determine their effect on the phenolphthalein test and vice versa. Of the 40 products, four were found to show a false positive result or an abnormality. These inconsistencies are attributable to the ingredients found in the four products and their chemical or oxidizing properties. Recognizing the characteristics of the irregular results can be of great help during testing in the laboratory.

Review of Several False Positive Error Rate Estimates for Latent Fingerprint Examination Proposed Based on the 2014 Miami-Dade Police Department Study

Author(s): Masha Signaevsky
Type: Article
Published: 2019, Volume 69, Issue 1, Page 059
Abstract:  In 2014, the Miami-Dade Police Department (MDPD) Forensic Services Bureau conducted research to study the false positive error rate (FPR) associated with latent fingerprint examination. They report that approximately 3.0% of latent fingerprint examinations result in a false positive conclusion. In their 2016 report, the Presidents Council of Advisors on Science and Technology (PCAST) advise that this estimate of the FPR be used to inform jurors that errors occur at a detectible rate in fingerprint estimation and declare that false positive conclusions may occur as often as 1 in 18 cases. In this paper, we review the MDPD study and design a simulation study to model the behavior of the participants in the MDPD study. We use our model to simulate the number of erroneous identifications that occur under any assumed FPR and compare the results to the actual number of erroneous identifications observed in the MDPD study. We conduct experiments associated with the error rates proposed by the MDPD and the Organization of Scientific Area Committees Friction Ridge subcommittee. We note that the results of these experiments indicate that none of the proposed FPRs are reasonable estimates of the true FPR associated with the MDPD study. We propose two solutions based on a Bayesian analysis of the data, each resulting in two separate FPRs. Our solutions are comparable to the estimates offered by the Noblis black-box study.

Back to Basics

Author(s): Sandy Siegel, CLPE
Type: Back to Basics
Published: 2019, Volume 69, Issue 1, Page 124
Abstract: Funny finds from all over in their own words.

JFI Abstracts from 2018

Issue 4: October-December 2018

Two Cases of Dendrochronology Used to Corroborate a Forensic Postmortem Interval

Author(s): James T. Pokines
Type: Case Report
Published: 2018, Volume 68, Issue 4, Page 457
Abstract:This report details two cases where the dendrochronology of tree roots was used in Massachusetts to provide a minimum postmortem interval (PMI) for a set of buried human remains. In both cases, the tree ring counts corroborated witness testimony regarding the approximate age of the burials; one analysis indicated a minimum of 27 years since burial, and the other indicated a minimum of 14.5 years since burial. Tree ring dating can fill an important role in minimum PMI estimation over intervals longer than can be covered by forensic entomology or other aspects of decompositional state, and tree root samples should be collected wherever they have a chance of aiding PMI estimation.

Photo Response Nonuniformity (PRNU) Meets Daubert Standards

Author(s):Aislynn MacKenzie; Walter E. Bruehs
Type: Case Report
Published: 2018, Volume 68, Issue 4, Page 467
Abstract: During United States of America v Nathan Allen Railey, photo response nonuniformity (PRNU) was used to identify a camera. This identification was challenged in an admissibility hearing to verify that the technology met the Daubert standard, setting a precedent for its use in future forensic examinations.

A New Method for Documenting Hertzian Fractures in Glass Windows

Author(s): Brent A. Horn
Type: Article
Published: 2018, Volume 68, Issue 4, Page 473
Abstract: Hertzian fractures, or cone fractures, caused by bullet perforations in glass windows can be useful in shooting incident reconstruction. However, they are difficult to photograph because of the transparent nature of glass. Standard glass documentation photographs prohibit determination of the deflection direction of light rays off fracture features, thus creating difficulty in determining the cone-bearing surface of the Hertzian fracture. This article presents a new method for photographing these fractures on various glass materials. Surface reflection photography (SRP) documents the contour-dependent nature of the surface and fracture, allowing the shooting reconstructionist to determine the bevel-bearing surface of the glass from the collected images without direct observation of the glass material. This method is applicable for annealed, tempered, laminated, and coated glass materials with both light and dark backgrounds.

Efficiency Assessment of Luminol-Based Formulations Using Bloodstains and Grayscale Intensity

Author(s): Valentin Carlier; Andy Bcue; Olivier Delemont
Type:Article
Published:Volume 68, Issue 4, Page 490
Abstract: Luminol is often used to detect latent bloodstains at crime scenes. Several formulations of luminol-based solutions are available. These formulations must be compared and assessed for their efficiency for use at crime scenes. Most studies consider spectrometric measurements, where the reaction is triggered and monitored in spectrometric cells. In spectrometric cells, the blood is liquid, and the luminol ismixed with the blood, not sprayed onto it. Conclusions made from spectrometric measurements may not be accurately transposed to the situations of luminescence encountered under crime scene conditions because the testing conditions do not replicate the crime scene. This study consequently proposes a photographic-based method for measuring the chemiluminescence from bloodstains sprayed with luminol. The photographs that were made during the current experiments were converted into grayscale to provide objective values of the intensity of the chemiluminescence, which was recorded every 5 seconds during a period of 10 minutes. This photographic protocol was used to record both the regular luminol solution and also the luminol-f luorescein mixture. Results showed that the proposed method can objectively quantify the chemiluminescence intensity. Furthermore, contrary to what previous research that was based on spectrometric laboratory measurements indicated, the luminol-fluorescein mixture was not more efficient than a regular luminol solution. Differences may be explained by the measurement strategy (spectrometric measurement versus photographic recording), the proposed approach being more representative of the way luminol enhances bloodstains at crime scenes.

Latent Blood Detection and STR Analysis of Samples Collected from an American Civil War Field Hospital

An Investigation into the Effect of Weight on Angle and Base of Gait

The Effect of Cyanoacrylate Fuming on Subsequent Protein Stain Enhancement of Fingermarks in Blood

Longevity of Tween 20-Based PhysicalDeveloper

Follow-up: Fingermark Development on Fired Cartridge Cases through the Electrodeposition of Gun Blue

Latent Print Processing of Glassine Stamp Bags Containing Suspected Heroin: The Search for an Efficient and Safe Method

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Issue 3: July-September 2018

Assessment of Friction Ridge Skin and Scars with a Focus on Latent Print Examination

Expert Fingerprint Testimony Post-PCASTA Canadian Case Study

This article summarizes the trials, the impact of the Presidents Council of Advisors on Science and Technology (PCAST) report Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods on expert testimony, and provides an explanation of an incorrect error rate reproduced by PCAST. As the RCMP learn from this court challenge, potential future changes to RCMP research, policy, and training are discussed.

Frequency of Insufficient Knowns in Comparison and Processing Cases

Author(s): Cavazos, Christopher
Type: Technical Note
Published: 2018, Volume 68, Issue 3, Pages 333-340
Abstract: This project was designed to calculate the frequency of insufficient known inked impressions in comparison and processing cases with at least one identifiable latent fingerprint. Insufficient known inked impressions are described as having poor quality, lacking the area needed to conduct a conclusive comparison, or a combination of the two. This study analyzed 256 cases from the Western Regional North Carolina State Crime Laboratory from 2004 to 2009 and 460 cases from the Raleigh North Carolina State Crime Laboratory from 2013 to 2015, for a combined total of 716 cases. This study showed nearly 20% of all cases involved had insufficient known impressions. A lack of friction ridge information being recorded in the known impressions was the main contributor to the determination of insufficiency.

Comparison of the Quantity and Overall Quality of Trace DNA Evidence Collected from Substrates Found at Crime Scenes

Author(s): Hogan, Chad; Van Houten, Lora Bailey; Coticone, Sulekha
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 341-347
Abstract: The ability to recover high-quality trace DNA samples from crime scenes depends on the characteristics of the contributor, the surfaces, the environment, and the time until recovery. In this study, saliva samples were deposited on various surfaces, followed by periodic swabbing at timed intervals for 3 months. The results indicate that porous surfaces (e.g., brick) provide lower amounts and quality of DNA as compared with smooth surfaces (e.g., plastic, glass).

Impact of Anti-Fingerprint Coatings on the Detection of Fingermarks

Author(s): Forchelet, Sandra; Bcue, Andy
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 348-368
Abstract: This study discusses the deposition and behavior of fingermark residue (eccrine, sebum-rich, and natural) on anti-fingerprint (AFP) coatings as well as the impact of these coatings on conventional detection techniques (cyanoacrylate fuming, small particle reagent, vacuum metal deposition). The preliminary conclusions show that (1) AFP coatings do not prevent the deposition of secretion residue, (2) the amphiphobic properties of AFP coatings may benefit the preservation and observation of latent marks, (3) AFP coatings do not hinder the application of conventional detection techniques, and (4) the impact of AFP coatings on ridge clarity is overall positive or limited, with differences of behavior between plastic-based coatings (negative impact mostly) and glass-based ones (positive impact mostly).

Detection of Fingermarks from Post-Blast Debris: A Review

Author(s): Smyth, Alexander; Sims, Mark R.; Holt, John
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 369-378
Abstract: Fingermarks, an important area of forensic investigations, are generally believed to be destroyed during explosive events. Therefore, post-blast investigations are rarely centered around fingermark evidence recovery to identify a suspect. In-depth research into the recovery of fingermarks from post-blast scenes is lacking. Only five research attempts have been published to date. These five publications are reviewed here. By summarizing the research to date, future experimental work can be conducted to build upon this fledgling research area to the point where a repeatable and successful technique may be discovered.

Comparison of Latent Print Proficiency Tests with Latent Prints Obtained in Routine Casework Using Automated and Objective Quality Metrics

Author(s): Koertner, Anthony J.; Swofford, Henry J.
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 379-388
Abstract: This study evaluates how well the quality of latent print proficiency test samples represent those encountered during routine casework and starts a conversation on what these data really mean. Currently, proficiency tests are designed to monitor the performance of laboratoriesfrom when the examiner receives the materials to when results are releasedto satisfy accreditation requirements and demonstrate the validity of the methods when applied to test samples representative of casework. In order to do this, the latent print samples are intended to mimic the quality or difficulty encountered during routine casework; however, there is a dearth of research to verify this claim. Subjective experience from the latent print community has been that proficiency tests offer higher quality and less complex examinations than those typically evaluated in routine casework. Sampling of latent fingerprints obtained from commercially available latent print proficiency tests and latent fingerprints obtained over the course of routine casework were collected and compared using objective latent print quality metrics. Results indicated that the quality levels of latent fingerprints from proficiency tests are generally higher quality, less complex, and do not represent the quality levels observed in routine casework.

Determination of Detection Sequence for Optimal Visualization of Blood Fingermarks on a Dark Surface

DNA recovery was more successful when the blood marks were first treated with cyanoacrylate. The first blood fingermark of the depletion series gave the best DNA result. Fresh fingermarks of up to a week, which were fixed with ethanol right before coloring with SPR-W, gave a slightly better DNA result.

Assessing the Appearance of Latent Print Distortion on Absorbent and Nonabsorbent Substrates

Author(s): Tate, David; Anderson, Elizabeth; Eller, Jesse
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 403-420
Abstract: Lateral movement, or shearing stress, may occur in a latent print. In this study, we examined lateral movement of a finger on copier paper (absorbent substrate) and lateral movement of a finger on porcelain tile (nonabsorbent substrate) to determine whether there were any observable differences in the appearance of impressions deposited in a specifically controlled direction (laterally). An attempt was made to control the matrix volume, duration of contact, and the absorption properties of the substrate for all trials. Results showed that visual clues (e.g., the intensity of the impression at the start of movement compared to the intensity of the impression at the end of movement, and the presence of a corona at the ending impression) could assist in determining directionality of finger movement on the absorbent substrate.

Preliminary Studies into the Secondary Transfer of Undeveloped Latent Fingermarks Between Surfaces

Author(s): Jabbal, Randeep S.; Boseley, Rhiannon E.; Lewis, Simon W.
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 421-437
Abstract: This study investigates the conditions under which undeveloped fingermarks will transfer between surfaces that have come into contact. Latent fingermarks were deposited on a glass surface, which was brought into contact with paper surfaces for varying periods of time and pressure. Subsequently, the paper was treated with a variety of development procedures including 1,2-indanedione-zinc, ninhydrin, Oil red O, aqueous Nile blue, and SMD II. 1,2-Indanedione-zinc was successful at detecting transferred fingermarks, with good contrast and ridge definition, observed when fresh fingermarks were transferred by contact with the secondary surface for a minimum of 24 hours under a 5.00 kg pressure. The high degree of clarity and contrast of the developed transferred fingermark made it difficult to differentiate as a secondary mark. Transferred marks can only be recognized as a mirror image when compared to a mark directly deposited from an individual.

Using Luminol to Detect Bloodstains Exposed to Fire, Heat, and Soot on Multiple Surfaces

Author(s): Akemann, Emma; Bushong, Lee C.; Jones, Ward M.
Type: Article
Published: 2018, Volume 68, Issue 3, Pages 438-453
Abstract: This article investigates the ability of luminol to detect bloodstains that have been exposed to fire, heat, soot, and water. Blood applied to drywall, appliance sheet metal, glazed tile, carpet, and wood was exposed to fire, followed by typical firefighter extinguishment. The results show that bloodstains on some surfaces that have been exposed to heat, fire, soot, or water may produce false negatives when tested with luminol.

Back to Basics

Author(s): Siegel, Sandy
Type: Back to Basics
Published: 2018, Volume 68, Issue 3, Page 456
Abstract: Funny finds from all over in their own words.

Issue 2: April-June 2018

Laterally Reversed Latent Prints Developed Using 1,2-Indanedione

Author(s): Brazelle, Shelly; Inlow, Vici; Leitner, Mary Lou
Type: Case Report
Published: 2018, Volume 68, Issue 2, Pages 161-170
Abstract: Laterally reversed latent prints that have been attributed to transfer from one surface to a second surface have been reported in cases where different processing techniques have been used on bags, books, and adhesive surfaces. Three cases demonstrating the existence of laterally reversed latent prints when no surface transfer has occurred are presented. Each case of a laterally reversed latent print was developed with the chemical reagent 1,2-indanedione. The increased use of 1,2-indanedione and the ability to develop laterally reversed latent prints demonstrate the need to address issues regarding recognition, documentation, reporting, and policy procedures.

Use of Gelatin Lifters and Episcopic Coaxial Illumination for the Recovery and Imaging of Latent Fingermarks from Various Surfaces

Author(s): Attard, Chantelle; Lennard, Chris
Type: Technical Note
Published: 2018, Volume 68, Issue 2, Pages 171-185
Abstract: A study was conducted to assess the effectiveness of gelatin lifters as a method of latent fingermark recovery. Such a capability may be important in covert operations where rapid, nondestructive techniques need to be applied. A preliminary trial was conducted to determine the best surface types for fingermark recovery using black gelatin lifts, with the resulting lifted impressions imaged using an optical method referred to as episcopic coaxial illumination (ECI). As expected, it was found that fresh, sebum-rich fingermarks on smooth, nonporous surfaces produced the best results. A more extensive study was then conducted using natural fingermarks from multiple donors and fingermarks aged for periods up to six weeks. Both black and white gelatin lifters were assessed, as well as the impact of reattaching the protective plastic film provided to cover the lifted impressions. The best results were obtained using black lifters applied to nonporous surfaces that contained sebum-rich, relatively fresh impressions (i.e., aged for a short period of time). Lifts that were left uncovered prior to ECI imaging also resulted in higher quality fingermarks. The use of a commercially available ECI accessory was found to be a cost-effective method for the recording of lifted impressions.

Variability of Class Characteristics Observed in Die Cut Outsoles Composed of Both Rubber and Textile Materials

Author(s): Gokool, Vidia A.; John, Jeremy A.; Koertner, Anthony J.
Type: Technical Note
Published: 2018, Volume 68, Issue 2, Pages 187-206
Abstract: This study examines the variability of certain manufactured features of unworn footwear outsoles that relate to their textile coverings. The manufacturing process that is used in producing the Sanuk Vagabond and Toms Classic involves die-cutting a sheet stock, which is composed of a mixed ethylene vinyl acetate and rubber compound with a textile layer faceted on top. The addition of the textile layer during the molding process reduces the amount of exposed mixed-rubber material to a dotted pattern of exposed area, thus creating a new feature that is variable to the class characteristics on the outsole. This manufacturing process introduces variance in outsole features from shoe to shoe. Measurements of the variabilities yielded statistical data that support the use of textile-induced outsole features in relation to outsole-imbedded features as an additional highly discriminating characteristic to be considered in footwear comparison examinations.

A Comparison of Hydrophobic Barriers for Casting Footwear Impressions in Water-Soluble Food Products

Author(s): Sabolich, Adam R.
Type: Technical Note
Published: 2018, Volume 68, Issue 2, Pages 207-221
Abstract: Eight different products were tested to determine a hydrophobic barrier that could best preserve a footwear impression in water-soluble food products. A control test was performed with no product used between the water-soluble food product and the casting product. Because many of the products sufficiently preserved the more pronounced three-dimensional features, a set of minor and individual features were isolated to gauge the efficacy of each product. The results were varied. Some products produced an even worse cast than the control; others preserved only the major features. The best results were obtained using the sequential treatment of Krylon Colormaster Crystal Clear Gloss Spray Acrylic -> Arrid XX Ultra Clear Aerosol Spray Antiperspirant and Deodorant -> Snow Print Wax.

Laser Bullet Trajectory Photography

Author(s): Lemasters, Timothy; Johnson, Daniel; Miller Brian
Type: Technical Note
Published: 2018, Volume 68, Issue 2, Pages 223-233
Abstract: The ability to capture laser bullet trajectory in daylight conditions is important. Most crime scene investigator trajectory kits do not include the necessary equipment for all conditions and should be augmented with higher powered laser pointers and neutral density filters. This technical note describes a method for consistent capturing of laser trajectory beams during daylight conditions.

Estimating Stature from the Measurements of Upper Limbs in the Indo-Mauritian Population

Author(s): Agnihotri, Arun Kumar; Tangman, Yannick
Type: Article
Published: 2018, Volume 68, Issue 2, Pages 234-255
Abstract: The aim of this study was to predict stature in the Indo-Mauritian population, when that the sex of the individual was unknown. Measurements [height (stature), upper limb length, upper arm length, forearm length, hand length, and the length of the second to the fifth fingers] of 200 young and healthy students (100 male and 100 females), aged 19 25, were taken using standard anthropometric instruments. A significant relationship was found between the stature and upper limb dimensions (adjusted R2 ranged from 67.63% to 80.91%), with the highest linear association observed for the upper right limb. The standard error of the estimate for stature prediction ranged from 3.70 cm to 5.15 cm for both sexes. Multiple linear regression equations using sex as a dummy variable gave better results than simple linear regression equations. Our regression models were sufficiently validated and highly efficient.

Assessing Phosphomolybdic Acid as a Fingermark Enhancement Reagent

Author(s): Davis, Lloyd W.L.; Bleay, Stephen M.; Kelly, Paul F.
Type: Article
Published: 2018, Volume 68, Issue 2, Pages 257-280
Abstract: The efficacy of an ethanolic solution of phosphomolybdic acid (PMA) was investigated as a latent fingermark visualization reagent, primarily on porous substrates. After treating samples and exposing them to ultraviolet radiation, the PMA solution was shown to develop fingermarks of high quality. Unlike the common amino acid reagents that are used for the development of fingermarks on porous substrates (e.g., ninhydrin and 1,8 diazafluoren-9-one), PMA stains a range of other compounds that are found in fingermark deposits, including lipids. The lysochrome diazo dye Oil Red O (ORO) was used for comparative purposes because of its application in staining some of the same components of fingermark residues for which PMA would be proposed. Initial results indicate that PMA is comparable to ORO at developing fingermarks on porous surfaces and may also have applications on nonporous surfaces.

A Comparison of Reverse Projection and Laser Scanning Photogrammetry

Author(s): Meline, Kimberly A.; Bruehs, Walter E.
Type: Article
Published: 2018, Volume 68, Issue 2, Pages 281-292
Abstract: Reverse projection photogrammetry has long been the standard by which height determination examinations have been conducted from security camera imagery. The uncertainty associated with this method is well understood. Laser scanning for this same use is gaining traction in the field of forensic video analysis as an alternative methodology. Laser scanning offers highly accurate measurements of the scene without the burden of placing a camera back into the same position it was in at the time of the crime. Additionally, the laser scanning methodology is not dependent on recreating the digital video recorders output aspect ratio, which is dependent on the recording device. An experiment was conducted to compare the accuracy of measurements that were obtained through both methods. Both methods yielded similar results, indicating further study should be conducted into laser scanning to determine how the error associated with laser scanning changes with different variables (e.g., the resolution of the imagery, distance from the camera, and the height of the camera). Further study is needed to define whether the technique passes thresholds that are suitable for court admittance.

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Author(s): Siegel, Sandy
Type: Back to Basics
Published: 2018, Volume 68, Issue 2, Page 296
Abstract: The most interesting pattern type on this hand is the tented arch in the left index finger. It is a classic tented arch of the up-thrust type. It is the bonus and not the main focus of this issue.

Issue 1: January-March 2018

Detection and Identification of a Latent Palmprint on a Cartridge

Author(s): Waldron, Michelle E.; Walls, Adrianne
Type: Correction
Published: 2018, Volume 68, Issue 1, Page 001
Abstract: On page 479 of the OctoberDecember 2017 issue of the Journal of Forensic Identification (volume 67, issue 4), the case report indicated that "of 2,727 cartridges that were processed, no latent prints that were suitable for comparison purposes were developed [1]." Although it is true that 2,727 unfired cartridges were processed in that study with no successes, an additional 259 discharged cartridges were also processed, with 1 success. (Read the article here)

A Case Report: The Analysis of Patent Prints Identified as Forgeries

Author(s): Sellenraad, Ashley
Type: Case Report
Published: 2018, Volume 68, Issue 1, Pages 003-009
Abstract: During the analysis of this case, three patent fingerprints on three separate checks were identified as being forgeries. A small experiment using friction ridge skin and black printers ink was conducted. The results of this experiment verified that the pliability of skin would not allow for an exact replication of a print, particularly around the edges, which was observed in the patent prints that were submitted in this case. It was determined that a stamp had been used as the method for depositing the patent prints on the checks.

Silver Nitrate Grade and Its Effect on Physical Developer Performance-- A Validation Study

Author(s): Coppes, Allison; Ramotowski, Robert S.; Jones, Brian A.; Manna, Michael E.; Chervinsky, Esther V.; Smith, Kim D.
Type: Article
Published: 2018, Volume 68, Issue 1, Pages 011-027
Abstract: Silver nitrate is a critical component of the physical developer (PD) reagent. Significant increases in the cost of silver nitrate in recent years have caused the United States Secret Services Forensic Laboratory to look for a more economical way to produce physical developer. One possible solution to this dilemma is to use a lower grade of silver nitrate, which typically has a lower cost. This study compared the quality of fingerprints produced on various paper substrates by three physical developer working solutions, each prepared using either the American Chemical Society (ACS), U.S. Pharmacopeia (USP), or technical grade of silver nitrate. It was determined that the less pure grades of silver nitrate produced approximately the same quality of fingerprints as the ACS grade, which is currently used in the authors laboratory for making PD working solutions. In the experiments comparing PD prepared using the ACS and USP grades of silver nitrate, the ACS grade was superior only 5% of the time, whereas the USP grade was chosen 27% of the time. In the experiments comparing PD prepared using the ACS and technical grades of silver nitrate, the ACS grade was superior only 10% of the time, whereas the technical grade was selected 17% of the time. For the majority of the sample comparisons, no difference in fingerprint quality was observed. The overall conclusion was that either USP or technical grade silver nitrate can be used in place of the current, and more expensive, ACS grade of silver nitrate.

Lay Understanding of "Identification": How Jurors Interpret Forensic Identification Testimony

Author(s): Swofford, H.J.; Cino, J.G.
Type: Article
Published: 2018, Volume 68, Issue 1, Pages 029-041
Abstract: In recent years there have been several discussions amongst forensic science policy makers, forensic practitioners, legal practitioners, and academia regarding the most appropriate means of expressing forensic conclusions, especially pertaining to source associations in the pattern evidence domains, to ensure proper articulation of the weight of the evidence to the fact finder. Central to these discussions is the use of the words "identification" or "individualization" to report positive associations between an evidence sample and a known sourceoften used to express the opinion that the two samples "were made by the same source". Proponents argue that the terms are appropriate provided that they are properly defined and caveated to be an expression of an opinion. Critics argue that the terms are inappropriate because they imply a weight of evidence that has not yet been empirically demonstrated and, given the historical use of the terms, simply avoiding the added phrase "to the exclusion of all others" is insufficient. An underlying question at the heart of this discussion, then, is how lay persons interpret such testimony. After polling 300 lay persons, we found that approximately 71% of potential jurors may be expected to interpret expert testimony containing the word "identification" (or "identified") to imply a single source attribution "to the exclusion of all others". The intent of this study is to provide preliminary data to inform the forensic science community on how the term "identification" may be interpreted by laypersons when used in the context of expert testimony and technical reports.

Author(s):Author(s): Schreel, Maralena; Stonehouse, April; Torres, Anne
Type: Article
Published: 2018, Volume 68, Issue 1, Pages 043-075
Abstract: A questionnaire was distributed to establish baseline knowledge on the use of scarred friction ridges in the latent print discipline. Questions were designed to evaluate the utilization and weight of scar features in the decision-making process and to assess the value of scars in a latent comparison. Twenty-nine latent print examiners participated in the 94-question survey. The results of this questionnaire showed that despite the lack of literature and formalized training, participants (1) were able to use their experience to make comparative decisions, including identifications, that were based on scar features; (2) were consistent in recognizing and assigning weight to scars; and (3) were able to use scars, or the absence of them, to substantiate their decisions.

Author(s): Brazelle, Mack; Brazelle, Shelly
Type: Article
Published: 2018, Volume 68, Issue 1, Pages 077-086
Abstract: This study examines the use of whorl slant in hand determination through whorl axis analysis. Two certified latent print examiners determined the whorl axis for 550 whorls. They found a higher percentage of right slant whorls in the right hand (92.7% and 93.8%) and a higher percentage of left slant whorls in the left hand (91.0% and 91.2%). A small percentage of whorls absent of any axis were reported in both hands. Interestingly, a higher percentage of right slant whorls were present in the left index finger, and a higher percentage of left slant whorls were present in the right index finger. Applying the chi-square test to overall whorl slant data from each hand demonstrated that using the whorl axis to determine hand orientation is statistically significant.

Differential Diagnosis of the Taphonomic Histories of Common Types of Forensic Osseous Remains

Can Intentionally Compacting a Clandestine Grave Make it More Difficult to Detect with a Soil Probe?

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