This article reviewed previous studies concerning psychophysiological detection of deception in which event-related brain potential(ERP) had been recorded as a response index. The usual dependent measures in detection studies are autonomic activities such as respiratory, electrodermal, and cardiovascular responses that are assumed to be correlates of the emotional state induced by crime relevant questions. Recently, however, researchers in this field have emphasized the importance of cognitive factors rather than emotional ones to detect guilt and this trend facilitates the use of ERP as a detection measure.
  Several ERP components have been identified and each functional significance during human information-processing has been well described. In the ERP-based detection studies, a component such as P3, N400, or CNV(contingent negative variation) have been used as a detection index. The P3 is elicited by rare and meaningful events that are relevant to the participant's task. The N400 component is elicited by semantic anomalies such as words that complete sentences falsely. The CNV has been variously described as related to expectancy, motivation, and attention. Although these three ERP components seem valid detection measures, the most promising index in the field practice is the P3 component because of its relative ease of recordings and large amplitudes. Moreover, in laboratory studies, correct detection rates by the P3 component are slightly higher than the rates by the conventional autonomic measurements.
  Several merits of using an ERP component as a detection index are summarized as follows: 1) advancement and elaboration in judgment of test results because ERP are specifically time locked to an event, 2) an improvement of the correct detection rate, 3) an improvement of test objectivity and reliability, and 4) counteracting countermeasures. Before the practical use of ERPs in the psychophysiological detection of deception, however, a method of artifact-free measurement of ERPs and a definite criterion of judgment for individuals must be established.

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  We analyzed monoamine metabolites concentrations in blood plasma of flashbackers who had a history of methamphetamine(MAP) abuse. Subjects were composed of 12 flashbackers, 8 non-flashbackers, 13 MAP users who were not experienced MAP psychosis, and 15 MAP non-users. Flashbackers and non-flashbackers had previously all experienced MAP psychosis. Flashbacks were mostly triggered by mild fear of other people. Plasma norepinephrine(NE) levels were higher in 12 flashbackers during flashbacks than during periods of normalcy. Also plasma NE levels during flashbacks were higher than those in the 13 users and 15 non-users. Plasma NE levels in flasbackers during periods of normalcy were higher than those in the 13 user controls. Other monoamine metabolites concentrations in blood plasma were not significantly different among the subject subgroups. These results suggest that repeated MAP use with threatening experiences may produce sensitivity of neurotransmitter systems including noradrenergicsystems to psychosocial stressors at pharmacologic levels. An increase in peripheral noradrenergic activity may be related to occurrence of flashbacks.

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  The purpose of this study is to examine the repetition of criminal modus operandi(M.O.) with the data of burglary, i.e., theft through breaking and entering. As the measure of the repetition, the probability that a suspect used the same M.O. in two incidents randomly chosen from previous ones, is calculated. As a result, suspects seem to choose M.O. used in previous incidents as they commit crimes repeatedly. Besides, some M.O. are used consistently over time, though the others change from one incident to the next. Similarity among each type of burglary is also examined by factor analysis.

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  Positive identification of unknown skeletonized victims lacking clinical records generally difficult. However, if their facial photographs could be obtained, their unknown skulls could be identified by the cranio-facial superimposition. The last two decades, video superimposition technique has widely been used for identifying unknown skulls. Although video superimposition will be the most superior technique, the means are expensive and unusual installation. Therefore, in Japanese local forensic science laboratories, the video superimposition installation is not popularly used. To solve the problem the authors attempted to identify an unknown skull by an inexpensive means of superimposition using a personal computer, a digital camera, an image-scanner and a photo-retouch-soft(Adobe Photoshop). The use of the personal computer with Adobe Photoshop allowed to capture a digitized image of the facial photograph with the image-scanner and an image of the skull with the digital camera. With the Adobe Photoshop, the digitized skull's images can be converted to a transparency so as to be overlaid on the digitized facial image and then be adjusted to their respective size. In order to investigate the reliability of our cranio-facial superimposition method, one skull was superimposed on facial photographs of the true person and 14 other people. The true person was correctly identified as the skull's owner and the 14 others were excluded. Hence, the authors insist that this method will be useful to demonstrate the consistency between skull and facial photograph for personal identification.
  The application of this superimposition method to three actual cases was also described.

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  Gunshot residues (GSR), which mainly consist of fired primer compound and propellants, remaining on a firearm were investigated by electron probe microanalyzer (EPMA) and Fouriertransform infrared spectroscopy equipped with a microscope (FT-IR). Sample collection and handling techniques were developed to analyze of GSR, both inorganic and organic components. The sample was washed with n-hexane at first. The obtained waste solution was filtered with a white membrane filter made from polyterafluoroethylene. Spherical particles and shapeless particles in various sizes and colors on the membrane were observed under an optical microscope with about 75 magnification. Lead, antimony and barium were usually detected from the spherical particles using EPMA, and it indicated that spherical GSR came from primer compound. On the other hand, shapeless particles were picked up using a fine needle and identified by FT-IR. This method was applied to a hand of a gun shooter and a shirt of the killed woman. The inorganic GSR was detected from the hand of a gun shooter and the organic GSR was found from the shirt. These procedures have some advantages, they are very simple, rapid, inexpensive, non-destructive and detected both primer compound and propellant.

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  The infrared spectrum of methamphetamine hydrochloride by diffuse reflectance spectroscopy was compared with that by transmission spectroscopy. The former spectrum remained unchanged after preparation of a KBr disc, while the latter changed with the elapse of time.
  The liquid sample drop method which is frequently used in diffuse reflectance spectroscopy simplified sample preparation, and purification in the measurement of the infrared spectrum of methamphetamine hydrochloride.
  Consequently, reflectance spectroscopic measurement by the liquid sample drop method using an auto-sample-changer made it possible to obtain the infrared spectra of many samples easily and quickly.

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  Sensitivity and specificity of commercially available Lewis typing monoclonal antibodies were examined for application to forensic blood typing. We have evaluated six pairs of the commercial monoclonal antibodies (anti-Le^a and anti-Le^b) by using the hemagglutination test and enzyme-linked immunosorbent assay (ELISA).
  Only one antibody could clearly detect Lewis type from erythrocytes by the hemagglutination test.
  Two antibodies could exactly detect Lewis blood type from saliva and semen by the ELISA method. Other four antibodies gave cross-reaction to Le(a-b-) type (secretor) body fluids.
  This result suggested that we need to select suitable monoclonal antibodies of Lewis typing for each evidential sample and each blood typing method.

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