The accuracy of geographic profiling for predicting a serial offender's home/base location was compared by using three different distance measures—the Euclidean distance, the Manhattan distance, and the Shortest route distance—using the data of 1,856 crimes committed by 124 residential burglars in Northern Tohoku area of Japan from 2004 to 2015. Logarithmic and the negative exponential coefficients were estimated as the distance decay function for each distance measure by using leave-one-out cross-validation. Also, search areas were calculated to compare the accuracy of geographic profiling. Results of the Friedman's test indicated significant differences in search areas of the three distance measures for the wide area group which consisted of offenders having a long distance between crime locations. The search area when utilizing the Shortest route distance was the smallest for the logarithmic function, whereas the search areas using the Euclidean distance and the Shortest route distance were smaller than the Manhattan distance for the negative exponential function. Results of the narrow area group did not indicate significant differences in search areas for the three distance measures. Therefore, it was concluded that geographic profiling might be improved by using the Shortest route distance when calculating the probability distribution for offenders committing crimes in a wide area that includes many edges, such as rivers, railroads, and mountains, as well as paths such as bridges and railroad crossings.

 Applications of ICP-QMS/QMS using H₂ as a reaction gas were investigated for the accurate and precise determination of Fe in glass fragments. The maximum signal to background ratio was calculated by dividing ion counts for the sample solution (50 ng mL^－1 Fe in 0.8 mol L^－1 HNO₃) by that obtained for a blank solution (0.8 mol L^－1 HNO₃) at H₂ gas flow rates of 8 and 6 mL min^－1 for m/z＝54 and 56, respectively. The obtained values for ⁵⁴Fe and ⁵⁶Fe in a certified reference glass material (NIST 612) under the optimized condition in the H₂ gas mode showed a good match with the reference value (51±2 μg g^－1) with a precision of <7.1％ by RSD. The number of indistinguishable pairs among the 13 sheet glass samples manufactured using the same production line was limited to 12 of 78 by comparison of only Fe concentrations measured using the method developed herein, demonstrating the potential contribution of Fe analysis to enhanced evidence collection.

 The isomers of fluoro-butyrylfentanyl, fluoro-isobutyrylfentanyl, and fluoro-methoxyacetylfentanyl, in which the position of fluorine on the N-phenyl ring varies, were synthesized, characterized, and differentiated by infrared (IR) spectroscopy, liquid chromatography/mass spectrometry (LC/MS), and gas chromatography/mass spectrometry (GC/MS). The isomers could be clearly differentiated by their IR spectra. In the LC/MS chromatograms, the separation of the fluoro-butyrylfentanyl and fluoro-isobutyrylfentanyl isomers was insufficient. However, in the GC/MS extracted ion chromatograms, all compounds were completely separated. The LC/MS and GC/MS mass spectra of the isomers were similar, demonstrating that it is difficult to distinguish the positional isomers of fluorinated fentanyl analogs by their mass spectra.

 Illegal distribution of cannabis products, such as cannabis-infused foods and e-liquids, are increasing in Japan. The main component of cannabis is tetrahydrocannabinol (THC). THC extracted from cannabis is regulated by the Cannabis Control Act, and chemically synthesized THC is regulated by the Narcotics and Psychotropics Control Act; therefore, it is important to identify the source of THC for judicial appraisal. Recently, the crime of cultivating cannabis has occurred frequently in Japan. Illegal cultivation is difficult to discover because there are cases in which cannabis is cultivated secretly in a room in apartments, etc. Cannabis is a plant that emits unique odors. Detection of the odor constituents can provide a breakthrough for the criminal investigation of cannabis cultivation. The purpose of this study was to identify cannabis products and utilize them for the criminal investigation of cannabis cultivation. Cannabis plants were cultivated from seeds and analyzed using both solid-phase microextraction (SPME) and solvent extraction. Fifty kinds of volatile components were detected by SPME and 21 kinds of refractory components were detected by solvent extraction in fresh cannabis plants. We found that terpenes were detected more strongly in cannabis buds than in cannabis leaves. Furthermore, sesquiterpenes were strongly detected from cannabis leaves and monoterpenes were strongly detected from cannabis buds. The most abundant components were β-myrcene, cis-β-ocimene, terpinolene, β-caryophyllene, trans-α-bergamotene, humulene and β-farnesene. Additionally, THC, cannabichromene, cannabigerol and tetrahydrocannabivarin known as cannabinoids, were detected in all the samples. For the identification of cannabis products, 7 kinds of terpenes and 4 kinds of cannabinoids are promising combinations. Additionally, these terpenes may be useful in the criminal investigation of cannabis cultivation.