Forensic examination of security features of the CDC-issued COVID-19 vaccination card and suggested improvements to minimize counterfeiting.

During the COVID-19 pandemic, the United States released the CDC-issued vaccination card to document the status of immunizations. It eventually was used as a verification system to allow patrons to safely access public venues. This is/was apparently a simple printed piece of paper with minimal security features which made it an easy target for counterfeiters with little expertise required. Those unvaccinated who wished to enter areas that required proof of the COVID-19 vaccine were soon finding alternative illegal methods to do so which led to public health concerns. This research was divided into two parts. Part A aimed to forensically identify the security features with a video spectral comparator and a stereomicroscope. Ten "known" blank cards were collected directly from dispensaries that administered the vaccine and 68 "unknowns" from individuals who received the COVID-19 vaccine. Part B aimed to evaluate the authentication systems employed by countries outside the United States to propose a model on how the vaccination card could be improved and what security features should be included for future instances requiring proof of immunization. The results revealed the CDC document was produced with minimal security features making the document prone to counterfeiting. Furthermore, based on the information collected from other countries' vaccination certificates, it is recommended to develop a dual authentication system, with digital and printable aspects, that contains a QR code linked to a database. Other security features may include a non-optical brightener substrate, security fibers, a watermarked logo, offset printing, and a geographical color-coded system.

Preliminary Study: DNA Transfer and Persistence on Non-Porous Surfaces Submerged in Spring Water.

Submerged items are often thought to lack evidentiary value. However, previous studies have shown the ability to recover DNA from submerged porous items for upwards of six weeks. The crevices or interweaving fibers in porous items are thought to protect DNA from being washed away. It is hypothesized that, because non-porous surfaces do not have the same traits that might aid in DNA retention, then DNA quantities and the number of donor alleles recovered would decrease over longer submersion periods. Additionally, it is hypothesized that DNA quantity and the number of alleles would be negatively affected by flow conditions. Neat saliva of known DNA quantity was applied to glass slides and exposed to stagnant and flowing spring water to observe the effects on both DNA quantity and STR detection. Results supported that DNA deposited onto glass and subsequently submerged in water experienced a decrease in DNA quantity over time, yet submersion did not have as strong of a negative effect on the detected amplification product. Additionally, an increase in DNA quantity and detected amplification product from designated blank slides (no initial DNA added) could indicate the possibility of DNA transfer.

Microbes in fingerprints: A source for dating crime evidence?

Interest in the human microbiome has grown in recent years because of increasing applications to biomedicine and forensic science. However, the potential for dating evidence at a crime scene based upon time-dependent changes in microbial signatures has not been established, despite a relatively straightforward scientific process for isolating the microbiome. We hypothesize that modifications in microbial diversity, abundance, and succession can provide estimates of the time a surface was touched for investigative purposes. In this proof-of-concept research, the sequencing and analysis of the 16 S rRNA gene from microbes present in fresh and aged latent fingerprints deposited by three donors with pre- and post-washed hands is reported. The stability of major microbial phyla is confirmed while the dynamics of less abundant groups is described up to 21 days post-deposition. Most importantly, a phylum is suggested as the source for possible biological markers to date fingerprints: Deinococcus-Thermus.

Evaluation of the loss of fingermark ridge clarity as a function of biological sex.

Latent fingermark ridge patterns result from imprinting sweat secretions onto receiving surfaces. However, little is known about the loss of skin moisture between immediate consecutive depositions and its effects on the visual quality of ridges and their degradation over time. In practice, it is recurrently assumed that the first touch should contain the most residue and, therefore, display the highest ridge quality. Also, it is expected to observe a gradual decrease in the quantity of residue deposited and, in turn, in the clarity of ridges. In this study, a total of 480 fingermarks were obtained from 20 donors, 10 males and 10 females, to assess the pattern loss of ridge quality across six successive impressions in a depletion series. Black magnetic powder (BMP) was utilized to visualize and photograph fingermarks on glass microscope slides. After image standardization, Quality Scores (QS) as well as metrics on ridge clarity were obtained from the FBI's Universal Latent Workstation (ULW). Data analyses revealed a significant drop in ridge quality over the six consecutive depositions, but notably after deposition four. No differences in ridge clarity between sexes were detected within the first three depositions although an effect was noted beyond this point. ULW proved to be an excellent and sensitive tool in detecting minute changes in ridge quality across the depletion series. These results may contribute in determining the chronological order of events and support further research in estimating time-since-deposition.

Evaluation of an inkless method for fingerprint recordings using hand sanitizer gel on thermal paper (Part II): Effect of time, temperature, and biological sex.

This article further investigates the suitability of an inkless method to obtain and maintain exemplar fingerprint recordings on thermal paper; in this case, stored for 1.5 years at different temperatures. Inkless impressions were (re-)examined by optical means via two independent methods. First, an automated metric from the FBI's Universal Latent Workstation (ULW) was adapted (i.e., BlueGreen color-coded maps) to evaluate visual differences among inkless fingerprint sets with respect to storage time, temperature, relative humidity, and biological sex. Additionally, a conventional assessment system was applied, a categorical quality score (QS) metric that ranges on a grading scale from 1 to 4. Results revealed that storage time (72 weeks), as well as a colder temperature (~ 3 ºC) and lower relative humidity (~ 12 %), had little impact on the preservation of ridge clarity when compared to freshly deposited counterparts. A biological sex effect was again detected, but its influence was not significant under certain conditions. Despite minor visual differences, the ridge clarity of the inkless impressions remained stable for the duration of the experiment. The stability and durability of the proposed inkless method were proven, becoming a potential alternative to the conventional black ink method.

Evaluation of 3D and 2D chronomorphometrics for latent fingermark aging studies.

Latent fingermark age determination is a relatively new subdiscipline of friction ridge pattern analysis that has the potential to ascertain two key pieces of information: the "who" and the "when" from a single evidence item. In this proof-of-concept study, the sensitivity and suitability of a series of 3D and 2D chronomorphometrics, ie, quantitative measurement of form as a function of time, are examined under various temperatures (55, 21, 4, and -20°C) at 6 months. 3D imaging with an optical profiler (OP) in tandem with a conventional 2D fingermark enhancing method, ie powdering with titanium dioxide, is the technique selected. From a chronomorphometric perspective, the 3D-OP detects micrometer variations in surface texture with regard to the heights (Sa and Ra) and volume (Vu) of the ridges, whereas 2D imaging provides information on color contrast (MI and IA), the fingermark visual quality score (QS), and the relative area extension of color-coded maps of ridge clarity (BlueGreen, BG). Statistical analyses have revealed different degrees of sensitivity of the 2D and 3D metrics for detecting the effect of temperature and time, being 3D the most discriminating. In these tested conditions, warmer temperatures (55 and 21°C) have shown the most impact on ridge degradation with the lowest levels observed at -20°C. The concurrent application of 2D and 3D metrics would be considered the best approach to advance the knowledge on fingermark aging processes and possible mathematical models.

The influence of biological sex on latent fingermark aging as examined by the color contrast technique.

This research further expands previous studies in which color contrast between ridges and furrows was examined as a possible age indicator for latent fingermarks. Here, the variable biological sex and its influence on aging were investigated. A total of 756 sebaceous-rich impressions from seven males and seven females were deposited on glass and polystyrene plastic and aged in the dark for three months. At nine discrete times, random fingermarks were visualized with a titanium dioxide-based powder (TiO2 ), photographed, and edited in Photoshop® to collect pixel color data. Two color contrast-related metrics, mean color intensity (MI) and intensity amplitude (IA), were analyzed to determine whether the aging processes of biological male and female fingermarks were equivalent. These metrics revealed that impressions from the different biological sexes behaved in a similar manner over time. However, significant effects between substrates were observed. Quadratic regression models best represented the aging trends based on the MI and IA metrics for both male and female fingermarks. The correlation coefficients (R) and coefficients of determination (R2 ) were moderate to strong for impressions on glass but weaker for plastic. These findings indicated that biological male and female fingermarks could be incorporated into a single universal age estimation model per substrate when utilizing color contrast as an age indicator. Nonetheless, future studies are needed to better understand aging processes on plastic when using this methodology and to determine the life expectancy (i.e., the potential for identification) of latent fingermarks beyond three months.

Evaluation of an inkless method for fingerprint recordings using hand sanitizer gel on thermal paper.

The main objective of this project was to assess an inkless method to collect reference (exemplar) fingerprints as a low-cost, portable, and hygienic technique; for temporary storage and as an alternative to the conventional black ink method. The tested inkless approach requires alcohol-based hand sanitizer gel as the medium and thermal paper as the substrate. The final quality and clarity of fingerprints were examined and compared between the two methods, especially on the basis of medium/substrate and biological sex effects. Two different evaluation systems of visual quality (clarity) were conducted to provide more reliable results: a quality score scheme (QS) and metrics from the FBI's Universal Latent Workstation (ULW). Fingerprints were obtained from 20 individuals (11 males and 9 females) between the ages of 20 and 40; a total of 240 impressions were evaluated. The results provide evidence that the inkless method produces identifiable fingerprints of equivalent quality to the standard ink method, although significantly better for males. The potential of the proposed technique as an alternative to the conventional ink method is proven and corroborated by the two independent systems of visual quality assessments.

Fingermark ridge drift: Influencing factors of a not-so-rare aging phenomenon.

Fingermark ridge drift is a random modification of (aged) fingermark patterns at a ridge scale. This phenomenon was previously proven to alter key elements used for identifications, such as the appearance of minutiae. Little is currently reported on the underlying factors contributing to its occurrence. The present study was designed to investigate further the variables of a previous study by including a total of 768 fingermarks from a male and female, two substrates (glazed ceramic tile and plastic), two distinct color powder developers (carbon black and titanium dioxide), three indoor lighting conditions (direct natural light, shade, and darkness), and two secretion types (sebaceous- and eccrine-rich). Fingermarks were aged for 2-72 days, powdered, photographed, and drift detected by three independent observers. All aged fingermarks (672) were compared relative to fresh fingermarks (96), and ridge drift was observed in 42 of 672 (6%) fingermarks, while 168 (25%) were reported as indeterminate results. While ridge drift was detected in multiple fingermarks across all independent variables, statistical analysis using a multinomial logistics model showed that only powder type, secretion type, and the substrate indicated a significant correlation with increased incidences of this phenomenon. There was no significant correlation with the donor, time since deposition, or the environmental lighting conditions used. The highest incidence occurred when carbon black powder was used on a plastic substrate (>10%). The average observation of ridge drift is 6% of samples supporting that this phenomenon is not a rare event, particularly considering the conservative analysis approach implemented.

Repeatability and reproducibility of the color contrast technique for fingermark age estimation applications.

This research complements previous studies in which color contrast between ridges and furrows of latent fingermarks was investigated as a potential aging parameter. In this case, the robustness of the technique has been tested by including five female and five male donors who deposited sebaceous-rich latent fingermarks onto ceramic tile and polystyrene plastic as well as flat and rolled inked fingerprints on commercially available ten-print cards. Fresh latent fingermarks were visualized with either carbon black or titanium dioxide powder (TiO2 ) and inked fingerprints were imprinted in succession without re-charging ink. The mean intensity (MI) and intensity amplitude (IA) metrics of the color histogram were collected from each image for statistical analyses. The goals were to detect any differences within and between the analysts' own interpretation of the protocol as well as examine how color contrast may be influenced by donor, substrate, biological sex, powder type, and the quantity of ink deposited. Results show that the color contrast metrics (MI and IA) are repeatable and reproducible and not affected significantly by donor, sex, deposition pressure, or distortion. However, the metrics were sufficiently sensitive to distinguish substrate and powder types and to detect different quantities of ink. The statistical analyses confirm and expand upon previous observations regarding the reliability of MI and IA as metrics that could eventually be used to estimate the age of a latent fingermark. At the same time, it was revealed that the technique needs further improvement and standardization by including a universal "white color standard" to conduct image comparisons.

Evaluation of latent fingermark color contrast as aging parameter under different environmental conditions: A preliminary study.

This research expands previous studies in which color contrast between ridges and furrows of powder-enhanced latent fingermarks was explored as a possible aging parameter. The main goal is to test the sensitivity of the technique across a predetermined set of factors. In this case, experiment factors have included two donors who deposited sebaceous- and eccrine-rich fingermarks onto ceramic tile and polystyrene plastic. These were developed with either black carbon or titanium dioxide powder (TiO2 ) over eight time periods (0-72 days) and aged under three light conditions (direct light, shade, and darkness). The mean intensity (MI) and intensity amplitude (IA) metrics of color were collected from each image for statistical analyses. Results show that color contrast is affected significantly by substrate, secretion, and powder types, with an interaction effect between the substrate and powder type on both MI and IA metrics. The degree of light exposure did not have a noticeable impact on distinguishing aging patterns of fingermarks by neither powder methods. Different aging patterns were detected between sebaceous-rich and their eccrine-rich counterparts for all light conditions using regression analysis. All eccrine-rich fingermarks exhibited little (or minimal) change in IA over time, whereas sebaceous-rich samples showed varied patterns, from significant decreases to slight increases. These findings confirm and expand previous observations on the potential use of MI and IA as metrics to study latent fingermark degradation patterns that could eventually be used to estimate the age of a fingermark.

A Small Population Study on Friction Skin Ridges: Differences in Ridge Widths Between Latent and Inked Fingerprints.

Morphological changes in the width of latent fingermark ridges occur naturally over time. This could be used to examine the aging process of latents and eventually estimate time of deposition. In a crime context, it is common practice to compare a questioned (aged) fingermark with a database of known (inked) prints. Therefore, in the absence of fresh fingermarks for aging purposes, it is of interest to reveal correlations between these two categories of fingerprints with regard to the widths of their ridges. The present study explores correlations of ridge widths between flat and rolled inked prints with latent fingermarks visualized with carbon black (CB) and titanium dioxide (TiO2 )-based powders among a small population of ten donors. Results revealed consistent differences between the ridge widths of latent and inked prints as well as flat and rolled impressions. Latent fingermarks visualized with CB and TiO2 powders showed ridges with comparable widths.

Latent Fingermark Aging Patterns (Part IV): Ridge Width as One Indicator of Degradation.

This fourth article of the series is taking an in-depth analysis at the visible aging of latent fingermarks regarding changes in ridge widths over time. The objective is to quantify and statistically describe significant ridge size variations under controlled indoor conditions. The effect of three environmental variables are examined: type of secretion (sebaceous- and eccrine-rich) and type of substrate (glass and polystyrene) when aged in three light conditions (direct natural light, shade, and dark). Prior to width measurements, fresh and aged fingermarks were powdered with titanium dioxide (TiO2 ) and sequentially photographed at predetermined times over 6 months. Three independent observers measured the ridges from thirty predetermined locations using strategically placed intersecting lines on the print. Results indicate that fingermarks deposited on glass are more resilient to degradation compared with those deposited on plastic. The presence of direct natural light plays a negligible role on degradation compared to secretion and substrate types.

Application of 3D Imaging Technology to Latent Fingermark Aging Studies.

In most latent fingermark aging studies, two-dimensional (2D) features are obtained from photo images, scans, or inked impressions. However, some relevant information is possibly being missed because fingermarks are three-dimensional (3D) objects that age in all three dimensions. A feature that has not been carefully examined is how the height of ridges changes over time. In this report, a 3D imaging technology-called optical profilometry-is introduced as a tool for the visual examination of the aging process. Optical profilometry is a nondestructive technology that allows the visualization and data acquisition of unprocessed latent fingermarks. Detailed ridge images and spatiotemporal data were successively obtained on the x-, y- and z-axis, delivering 3D topographical information. OP was able to detect the loss of ridge heights over time. The feasibility of employing this technology to collect data on the aging process of ridges has been proven.

Ridge Width Correlations between Inked Prints and Powdered Latent Fingerprints.

A methodology to estimate the time of latent fingerprint deposition would be of great value to law enforcement and courts. It has been observed that ridge topography changes as latent prints age, including the widths of ridges that could be measured as a function of time. Crime suspects are commonly identified using fingerprint databases that contain reference inked tenprints (flat and rolled impressions). These can be of interest in aging studies as they provide baseline information relating to the original (nonaged) ridges' widths. In practice, the age of latent fingerprints could be estimated following a comparison process between the evidentiary aged print and the corresponding reference inked print. The present article explores possible correlations between inked and fresh latent fingerprints deposited on different substrates and visualized with TiO2 . The results indicate that the ridge width of flat inked prints is most similar to fresh latent fingerprints, and these should be used as the comparison standard for future aging studies.

Forensic intelligence applied to questioned document analysis: A model and its application against organized crime.

The capability of forensic sciences to fight crime, especially against organized criminal groups, becomes relevant in the recent economic downturn and the war on terrorism. In view of these societal challenges, the methods of combating crime should experience critical changes in order to improve the effectiveness and efficiency of the current resources available. It is obvious that authorities have serious difficulties combating criminal groups of transnational nature. These are characterized as well structured organizations with international connections, abundant financial resources and comprised of members with significant and diverse expertise. One common practice among organized criminal groups is the use of forged documents that allow for the commission of illegal cross-border activities. Law enforcement can target these movements to identify counterfeits and establish links between these groups. Information on document falsification can become relevant to generate forensic intelligence and to design new strategies against criminal activities of this nature and magnitude. This article discusses a methodology for improving the development of forensic intelligence in the discipline of questioned document analysis. More specifically, it focuses on document forgeries and falsification types used by criminal groups. It also describes the structure of international criminal organizations that use document counterfeits as means to conduct unlawful activities. The model presented is partially based on practical applications of the system that have resulted in satisfactory outcomes in our laboratory.

Latent Fingermark Aging Patterns (Part III): Discontinuity Index as One Indicator of Degradation.

This article is the third in a series of reports exploring quantifiable visual parameters of the aging process of latent fingermarks. On this occasion, research is focused on the occurrence of ridge discontinuities (i.e. breakages) as a function of time. Experiment variables included type of secretion (eccrine and sebaceous), substrate (glass and plastic), and exposure to natural light (dark, shade, and direct light) over a 6 months period. Fingermarks were sequentially visualized with titanium dioxide powder, photographed, and the number of naturally occurring ridge discontinuities subsequently evaluated. A semi-quantitative value, named Discontinuity Index, was used to better characterize this aging parameter. Results indicated that ridges of sebaceous depositions on glass were generally less affected by the environmental conditions compared with those on plastic surface. In addition, aging in darkness was not always the best condition for preservation, and the direct exposure to light seemed not to affect the degradation under certain conditions.

Latent Fingermark Aging Patterns (Part I): Minutiae Count as One Indicator of Degradation.

The authors are exploring degradation patterns of latent fingermarks over time which can be quantitatively determined in a predictable manner by visual means. Several physical degradation parameters for assessing this hypothesis are evaluated. This article analyzes the parameter "minutiae count" as a function of time. Experiment variables included were secretion type (sebaceous-rich and eccrine-rich), substrate (glass and plastic), and exposure to light (dark, shade, and direct light). Depositions were sequentially visualized with Titanium Dioxide powder over a period of 6 months, photographed, and number of minutiae recorded. Results revealed a significant decrease of minutiae for eccrine-rich marks on glass but insignificant for sebaceous-rich marks on the same surface. However, significant degradation was observed for both types of secretions on plastic. The authors conclude that the distinctive prevalence of minutiae changes over time indicates with a high degree of certainty the hypothesis is valid and deserves additional exploration.

Latent Fingermark Aging Patterns (Part II): Color Contrast Between Ridges and Furrows as One Indicator of Degradation.

Currently, no established methodology exists to determine degradation patterns of latent fingermarks by visual means. This article is the second in a series of reports exploring quantifiable degradation-related parameters, which focuses on color contrast changes between fingermark ridges and furrows over time. Experiment variables included type of secretion (eccrine and sebaceous), substrate (glass and plastic), and exposure to natural light (dark, shade, and direct light). Fingermarks were sequentially visualized with titanium dioxide powder and photographed. Image histogram profiles were evaluated and combined with statistical analysis of color data values. Results indicate that sebaceous depositions on glass were generally less degraded by the effect of environmental conditions compared with those on plastic. In addition, aging in darkness was not always the best condition for preservation, and direct exposure to light seemed to inhibit visual degradation under certain conditions. Overall, the technique provided sufficient sensitivity to discern degradation patterns of fingermarks.