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Textiles are a commonly encountered source of evidence in forensic cases. In the past, most research has been focused on how textiles affect the decomposition process while little attention has been paid to how the decomposition products interact with the textiles. While some studies have shown that the presence of remains will have an effect on the degradation of clothing associated with a decaying body, very little work has been carried out on the specific mechanisms that prevent or delay textile degradation when in contact with decomposing remains. In order to investigate the effect of decomposition fluid on textile degradation, three clothed domestic pig (Sus scrofa domesticus) carcasses were placed on a soil surface, textile specimens were collected over a period of a year and were then analysed using ATR-FTIR spectroscopy and GC-MS. Multivariate statistical analysis was used to analyse the data. Cotton specimens not associated with remains degraded markedly, whereas the samples exposed to decomposition fluids remained relatively intact over the same time frame. An investigation of the decomposition by-products found that the protein-related bands remained stable and unchanged throughout the experiment. Lipid components, on the other hand, demonstrated a significant change; this was confirmed with the use of both ATR-FTIR spectroscopy and GC-MS. Through an advanced statistical approach, information about the decomposition by-products and their characteristics was obtained. There is potential that the lipid profile in a textile specimen could be a valuable tool used in the examination of clothing located at a crime scene., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

In crime scene reconstruction, it is often necessary to differentiate "contact transfer" and "spatter" bloodstain patterns found on clothing. Current methodologies, however, are qualitative and prone to context bias. In this work, we demonstrate that microscopic inspection of the stain orientations provides a quantitative differentiation of bloodstains resulting from spatter versus contact transfer. Specifically, common knitted fabrics are comprised of parallel rows of left loop legs, in an upward diagonal orientation (/), and right loop legs in a downward diagonal orientation (\). Our microscopic examination of more than 65,000 individual stained loop legs shows that spatter stains are approximately evenly distributed between left and right loop legs, but contact transfer stains are unevenly distributed: depending on the type of surface contacted, as many as 82% of the stains were preferentially located on the left loop legs. We further show that in these fabrics the left loop legs protrude further out than the right loop legs by approximately 50 μm, indicating that the observation of left loop legs preferentially stained over right loop legs is associated with the topography of the fabric. These findings suggest that microscopic quantification of the relative loop leg stain distributions could provide an objective means of differentiating contact transfer versus spatter patterns in crime scene reconstruction., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Clothing damage analysis is an integral part of the examinations carried out in sexual assault type cases. This analysis can be used to corroborate different versions of events and is at its most powerful in elucidating false allegation cases and consent cases. The purpose of this study was to determine to what extent people with varying levels of forensic awareness, experience and training could correctly carry out damage analysis. Two participant groups were asked to take part in this study. Group A ('forensic group') comprised participants at a forensic science conference, and Group B ('student group') comprised students undertaking a degree course in Forensic Science. Each group was given a practical workshop consisting of a lecture outlining common fabric types and general features observed in different damage types. Each participant was subsequently shown 25 pieces of 'damage' and asked to identify both the type of fabric construction (knit or weave) and the type of damage (cut, tear, rip, wear and tear). The ability to identify fabric construction and damage types varied within the two groups studied and across the groups. The forensic group performed better both in fabric and damage assessment than the student group. This paper suggests a systematic approach to clothing damage analysis to maximise the benefits that can be obtained from this area of forensic science and to minimise the subjectivity within the field.

This study reports the persistence behaviour of human scalp hairs under a number of different circumstances. The effects of artificial dyeing of hairs, the presence or absence of roots and different types of fabrics on the persistence of hair on a variety of garments were investigated. The garments were made from cotton, polycotton, cotton/acrylic, polyester and wool. The results indicated that neither artificial dyes nor the presence or absence of roots had statistically significant effects on the persistence of hair. In contrast, the type of fabric had a major impact and it was found that, generally, hairs persist longer on rougher fabrics. The rate of loss of hairs from non-woollen fabrics during normal wear was found to follow an exponential decay curve. In contrast, the rate of loss from the woollen garments was quite linear, indicating a constant, even loss, and thus suggests that a different process is involved in the persistence of hairs on woollen garments from that on non-woollen garments. The speed at which hair was lost from fabrics decreased in the order polyester, cotton/acrylic, polycotton, cotton, smooth wool, rough wool, so that wool gives the best chance of recovering samples of hair. Due to the uniqueness of each case, it is advised that caution be used when making any interpretations and before drawing any conclusions.

The influence of the drying position and time on the persistence of gunshot residues (GSR) on fabrics was investigated. Powder tattooing from a 40 cm shooting distance on targeted fabrics were slightly wetted using a spray and dried for 3 h or 48 h in horizontal or vertical positions. The GSR particles were visualised using IR fluorescence with a Video Spectral Comparator (VSC) and automatically counted with a software before the wetting and after the drying stages. While a significant rate of GSR particles (up to 22%) were lost, it was mainly due to the wetting procedure rather than the drying stage. No statistically significant difference was observed between the drying positions, indicating that both drying positions can be used in practice to dry slightly wet fabrics. The drying time had no influence on the loss, and the GSR distribution was not significantly influenced by either factor (i.e., time and position). • Gunshot residue loss was studied on fabrics shot at a 40 cm distance and sprayed with water. • The drying position for slightly wet clothes had little to no influence on the GSR loss. • No significant particle displacement was observed between the upper and lower half of the targets. • Drying will not significantly influence the estimation of the shooting distance. • No contamination was optically detected on blank fabrics during the drying process. [ABSTRACT FROM AUTHOR]

Forensic palynology has been important in criminal investigation since the 1950s and often provides evidence that is vital in identifying suspects and securing convictions. However, for such evidence to be used appropriately, it is necessary to understand the factors affecting taphonomic variability (i.e. the variability in the fate of pollen grains before they are found during forensic examination). Here, we test the relative amount of pollen retained on clothing after a period of simulated light or heavy wear based on pollen and fabric characteristics. We also test the efficiency of forensic laboratory protocols for retrieving pollen from fabrics for analysis. There was no statistically significant difference in retention of fresh or dried pollen on any fabric type. There was a substantial difference in pollen retention according to wear intensity, with considerably more pollen being retained after light wear than after heavy wear. Pollen from insect-pollinated species was retained at higher concentrations than pollen from wind-pollinated species. This pattern was consistent regardless of wear intensity but pollination type explained more of the variability in pollen retention after light wear. Fabric type was significantly related to pollen retention, but interacted strongly with plant species such that patterns were both complex and highly species-specific. The efficiency of removing pollen with the standard washing protocol differed substantially according to plant species, fabric type, and the interaction between these factors. The average efficiency was 67.7% but this ranged from 21% to 93%, demonstrating that previous assumptions on the reliability of the technique providing a representative sample for forensic use should be reviewed. This paper highlights the importance of understanding pollen and fabric characteristics when creating a pollen profile in criminal investigations and to ensure that evidence used in testimony is accurate and robust. [ABSTRACT FROM AUTHOR]

Abstract: Blunt force assault is a growing issue worldwide. In New Zealand, recorded cases of grievous blunt force assault increased steadily from 1011 in 1999 to 2139 in 2008 . In many cases of blunt force assault victims are struck on parts of their body covered by clothing, yet the use of damage to apparel as forensic evidence largely appears to have been overlooked. The current research investigated blunt force impact (BFI) damage in common apparel fabrics and the effects prior and post-laundering had on this damage. Two 100% cotton fabrics (single jersey knit, bull drill) were impacted as single and double layers using an impactor representative of a hammer face, the force transmitted through specimens was measured and impulse calculated. Impacting and laundering were completed cumulatively to establish the effects of impact damage on new, dimensionally stable (laundered 6 times) and aged fabrics (laundered up to 30 times), and the effects of laundering on impacted specimens. BFI left recognisable patterns of damage in specimens, although the extent of this damage varied. Laundering after the impact event altered the visible and microscopic damage. Laundering previously impacted fabrics produced holes in some specimens and some fibres exhibited failure characteristic of blunt force impact. [Copyright &y& Elsevier]