Capillary electrophoresis (CE) is now widely used as a separation and detection technique, due to its high peak resolution and simple operation. Since the analytical equipment had been commercialized in the early 1990's, CE has been introduced to the field of forensic toxicology. Various CE methods have been developed, such as simultaneous drug detection and chiral analysis of drugs and metabolites, and applied to real forensic examination. This review surveys the status of presentations on CE techniques in forensic toxicology, and introduces the CE methods performed in the author's laboratory for forensic examination on poisoning cases. The authors propose the practical use of CE in forensic toxicology as a means of a simple screening method for toxic substances, and quantification for target compounds or counter cations of hazardous anionic compounds by taking advantage of CE methods in simplicity, rapidity, quantification accuracy and wealth of separation conditions.

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  The modified mixed cell agglutination reaction (MCAR) method using mouse monoclonal antibodies was applied to ABO blood grouping of various forensic specimens. Pretreatment of several specimens was necessary. For example, fatty specimens such as soft tissues and bones could be fixed on the sample holder (two-sided adhesive tape) following removal of the fat with chloroform. Diluted samples could not be analyzed until the sample was eluted with distilled water or chloroform-methanol solution and concentrated on cotton threads. Hair roots and nails had to be sliced thinly. Following the pretreatment of the specimens, the same results were obtained by the modified method as by the conventional MCAR method using human polyclonal antibodies.

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  Visualization methods for a latent face impression on an expanded airbag in a collision of vehicles were experimentally examined. In order to make latent face impressions for experiments, a face of the same person was pressed against various base cloths of airbags. The base cloth used for a vehicle's airbag is generally made of nylon 66 fibers. However, some base cloths are coated with silicone resin or other materials to adapt to certain specifications. Taking into account the surface characteristics of base cloths, two methods, ruthenium tetroxide gas fuming method (RTX method) and Victoria Pure Blue staining method following cyanoacrylate ester vapor fuming (CA-VPB method) were examined for visualizing these latent face impressions. As a result, the latent face impression, called a “faceprint”, was a brown or black-stained image using the RTX method and a pale blue or dark blue-stained image using the CA-VPB method. The suitable method for visualizing a “faceprint” needed to be selected depending on the surface characteristics of base cloths. Thus, it was considered that the visualization of a latent “faceprint” was possible by using the suitable method for the condition of the expanded airbag, and this technique will be applicable to identify the driver in the traffic accident investigation.

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  The morphometric matching method for identifying persons from surveillance images using a computer-assisted facial image identification system has now been introduced to actual criminal casework. However, it is still sometimes a laborious task to rapidly distinguish a criminal from a number of suspects using the existing current facial identification system. Therefore in this study new software, which automatically adjusts the orientation of 3D face images in the database, was designed and its availability was experimentally evaluated as a preliminary step of an automatic face image identification system. From a total 5000 superimpositions of the 2D face images of 50 subjects which were compared automatically with the 3D face images of 100 suspects, only 18 face images of suspects (0.4%) showed inadequate orientation compared to their corresponding 2D face images for recognition purposes. From this experiment, it is concluded that the software developed will be applicable to the automatic adjustment of facial orientation in the 3D face image database and this is anticipated to improved the efficiency of policing in Japan as 3D imaging systems are deployed.

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  This study was aimed at evaluations of the blast characteristics by the arrival time of blast wave in the air. Some experimental explosions with small explosives less than a hundred gram were carried out in an explosion chamber. The signal from a handmade blast switch, which used aluminum foil as a blast-pressure acceptor, showed the same time to the edge position of time-pressure waveform observed by piezoelectric pressure sensor. It meant the arrival time of shock wave could be measured by the blast switch. According to the result of some experiments with several weights of Composition C-4, it was recognized that the arrival time apparently followed Sachs' scaling law because the plots of scaled arrival time against scaled distance came together on a line. The performance of Chlorate explosive, a mixture of potassium chlorate and sugar, was examined. The Composition C-4 equivalence of the chlorate explosive was led by two parameters that were peak overpressure and arrival time. The values 42.3% and 36.0% were given by the two parameters respectively.
  A measuring method of the arrival time for explosion accompanied with fragments was also examined. Composition C-4 put in a round-bottom flask was applied to the experiment. While the face-on blast switch was interfered by numerous glass particles scattered by the explosion, the side-on blast switch could avoid the glass particles clearly. The result suggested that the arrival time could be measured in spite of an explosion with scattering of fragments by the side-on blast switch.

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  A method for expressing the hair form of Japanese head hair in the form of numerical data was investigated with regard to inter-individual comparisons, and the utility of the method was evaluated based on the screening of experimental evidential hair samples by cluster analysis.
  The four characteristics used for the quantification of hair form included a basic characteristic (5 categories), an additional characteristic (4 categories) and 2 peculiar morphologies (3 categories). The hair forms of Japanese head hair were expressed by 448 combinations of these 12 categories. In addition, two numerical features were used as numerical data related to hair form as follows; the length and number of curves facing an assumed straight-line drawn between the tip and root ends of a hair image copied on the paper. This numerical feature was newly designed for this study.
  For confirming the availability of hair form for a hair comparison, the inter-individual comparison of Japanese males was investigated by a discrimination analysis using 13 variables, 11 values obtained by quantification and 2 numerical features. Head hairs from Japanese males were classified with a high level of discrimination between 2 individuals based only on hair form. Since the screening of evidential hair samples was investigated by a cluster analysis using 13 variables, in an experimental model of 40 evidential hair samples derived as an extra hair sample from 8 individuals, hair samples from 8 individuals were successfully discriminated using a cluster analysis.
  It was confirmed that a morphological examination represents an important tool for use in forensic hair comparison and that hair form is indispensable for interpreting the similarity of morphological features between known control hairs and evidential hairs.

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  In this report, we propose a seal-identification method using photo-retouching software (Adobe Photoshop).
  We devised a procedure by which one can create an outline of the image of a known seal by the “path” function and compare it by superimposing it over the image of the questioned seal. A Photoshop path expresses the range of an image with vector data.
  To examine the usefulness of this method, we evaluated the degree of precision in detecting an outline as well as the degree of distortion due to the rotation of the path, and then simulated a seal identification.
  The results showed that this method had a sufficient degree of precision in identifying seals. The method has two major advantages: faster and easier processing than the method by photograph and accuracy in reproducing the testing process by recording its procedure.

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  Shoeprints on soil or sand were lifted clearly with a quick setting resin. This resin, called Scandiquick, has been developed for metallographic embedding and consists of one powder (dibenzoyl peroxide, A) and one liquid (methyl methacrylate, B).
  Scandiquick was mixed in a volume ratio of two parts A and one part B using two measuring spoons, and both components were stirred thoroughly for approximately 30 seconds. Then the casting mixture was poured onto shoeprints. The resin set very quickly within 10 minutes and a clear impression appeared on it.
  The lifting method of shoeprints with Scandiquick has the following merits compared to that with plaster, which is the most popular for lifting shoeprints.
  1) This resin is especially effective for lifting shoeprints at the crime scene where water is not available.
  2) The set resin is light and tough, therefore, is easy to carry, handle and store.
  3) The impression of shoeprints can be photographed with transmitted light because the polymerized block has a slightly transparent appearance.

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  This study focuses on identification of bullets with three-dimensional data of landmark impressions. Generally, forensic scientists identify bullets by optical tools. For example, a comparison microscope, a CCD camera and photographs etc. Although these approaches are very essential and effective, the appearance of a striation depends on an illumination system in these methods. Therefore, there might remain some problems in the database that consist of only photometric data. On the other hand, 3D data of impressions on fired bullets are expected to possess generality and objectivity for forensic identification because the database that consists of geometric data is perfectly independent of any illumination. In this study, I used a confocal microscope as a 3D measurement device. I examined two jacketed bullets fired from a 0.25 caliber gun and six jacketed bullets fired from three 0.32 caliber guns. Each bullet had six landmark impressions, and there were twenty-four pairs of landmark impressions to be compared. The texture of a landmark impression is uniform along the direction of the scratch. It is expected that 3D profile is also uniform along the direction, so averaging 3D data along the direction can reduce an influence of measurement error. The averaged profile, shown as a 2D curve, fills the role of a characteristic profile. The 2D comparison of these profiles serves as bullet identification. Minute variations that form vivid striation were not shown clearly because of the averaging procedure. However, the comparisons of 24 pairs made it clear that global shapes of two profiles from the same origin coincide. Therefore, a sectional shape of a landmark impression would be a useful method for bullet identification when the bullet is not deformed and 3D shape of an impression is a little unique.

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  We report that a new type of l (−)-methamphetamine (MAMP) tablet recently found in Tochigi Prefecture is an abused drug of a new class. This tablet contains not only the stimulant l (−)-MAMP but also the stimulant caffeine and the anaesthetic ketamine. The constituent is the mixing ratio of 3.7% (approximately 13 mg) for l (−)-MAMP, 40.0% (approximately 140 mg) for caffeine and 9.1% (approximately 32 mg) for ketamine per one tablet. We are worrying about regular use of this new tablet as well as the traditional d (+)-MAMP crystal because these substances exhibit habituation and addiction, though its constituents were not detected from the urine specimens of a subject.

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