Raman spectroscopy and the forensic analysis of black/grey and blue cotton fibres Part 1: investigation of the effects of varying laser wavelength

Raman spectroscopy was investigated to determine the optimal conditions, mainly laser wavelength/s, for the analysis of the commonly encountered black/grey and blue cotton fibres dyed with reactive dyes. In this first part, a single blue cotton fibre, its three dye components, and an undyed cotton fibre were analysed with five different laser wavelengths from two different Raman microprobe spectrometers. The quality of the spectra, fibre degradation and speed of acquisition were used to determine that, under the conditions used, the 785 and 830 nm lasers gave superior results. The 632.8 nm laser wavelengths provided good results with little acquisition time and no spectral degradation. Results indicate that, at least, the major dye component could be identified using Raman spectroscopy.     

Thermal imaging and the fourth amendment:Kyllo v. U.S.

The Fourth Amendment protects persons from unreasonable searches and seizures. The extent to which the availability of new technology will impact this protection is an evolving area. One practice, police use of thermal imaging technology, has engendered substantial division in the courts. Recently, however, the United States Supreme Court addressed this issue in the case of Kyllo v. U.S. (2001). The Court determined that the pre-warrant use of thermal imaging machinery was a “search” under the Fourth Amendment and, thus, unconstitutional in nature. This paper traces the case development and examines the issues raised therein.     

AMPFlSTR Identifiler STR allele frequencies in Tanzania, Africa

POPULATION:  Identifiler—Employees and students of Muhimibili University College of Health Sciences in Dar es Salaam representing 19 widely distributed administrative districts and 42 tribes within the country.     

A forensic laboratory tests the Berkeley microfabricated capillary array electrophoresis device

Miniaturization of capillary electrophoresis onto a microchip for forensic short tandem repeat analysis is the initial step in the process of producing a fully integrated and automated analysis system. A prototype of the Berkeley microfabricated capillary array electrophoresis device was installed at the Virginia Department of Forensic Science for testing. Instrument performance was verified by PowerPlex 16 System profiling of single source, sensitivity series, mixture, and casework samples. Mock sexual assault samples were successfully analyzed using the PowerPlex Y System. Resolution was assessed using the TH01, CSF1PO, TPOX, and Amelogenin loci and demonstrated to be comparable with commercial systems along with the instrument precision. Successful replacement of the Hjerten capillary coating method with a dynamic coating polymer was performed. The accurate and rapid typing of forensic samples demonstrates the successful technology transfer of this device into a practitioner laboratory and its potential for advancing high-throughput forensic typing.     

Postmortem changes of human bodies on the bathyal sea floor--two cases of aircraft accidents above the open sea

Forensic taphonomy in the marine context recently received growing attention. However, only limited information is available about the fate of human bodies at greater sea depth. Following two fatal aircraft accidents (west of Namibia, south of Sicily) human remains were recovered from a depth of 540-580 m (both cases) after 3 months (Namibia)/34 days (Sicily). In the Namibia case fully skeletonized bones were lifted. In the Sicily case a complete, dressed body was found exhibiting a partially skeletonized skull, starting adipocere formation and pink teeth. The rate and mode of decomposition of human bodies in the deep sea varies considerably and is mainly influenced by the local faunal composition. Of special relevance for the understanding of both cases was the oceanographic observation that the highly efficient necrophageous lyssianassids are abundant off Namibia but are rare in the Mediterranean, emphasizing the importance of collaboration of forensic and marine scientists in such case work.     

Assertions of “Future Dangerousness” at Federal Capital Sentencing: Rates and Correlates of Subsequent Prison Misconduct and Violence

The federal prison disciplinary records of federal capital inmates (n=145) who were sentenced to life without possibility of release (LWOP) by plea bargain, pre-sentencing withdrawal of the death penalty, or jury determination were retrospectively reviewed (M=6.17 years post-admission). Disaggregated prevalence rates were inversely related to infraction severity: serious infraction =0.324, assaultive infraction =0.207, serious assault =0.09, assault with moderate injury =0.007, assault with major injuries or death =0.00. Frequency rates of misconduct were equivalent to other high-security federal inmates (n=18,561), regardless of infraction severity. Government assertions of "future dangerousness" as a nonstatutory aggravating factor were not predictive of prison misconduct. These findings inform federal capital risk assessments and have public policy implications for procedural reliability in death penalty prosecutions.     

Validation of an ion mobility spectrometry (IMS) method for the detection of heroin and cocaine on incriminated material

The validation of a qualitative ion mobility spectrometry (IMS) procedure for the detection of trace amounts of heroin and cocaine on incriminated material using a vacuum cleaner for sampling is presented. The limit of detection, the limit of decision, selectivity and robustness were determined. As an approach, robustness was determined using ionizational interferences and matrix effects. By using this simple sampling procedure, a positive result for incriminated clothes needs a contamination of 250ng cocaine and 1000ng heroin, respectively.