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The aim of this work was the classification of fresh lubricants for forensic science field. The seventy five kinds of lubricants were analyzed three times by GC/MS. And each lubricant (class) had three TIC data. Lubricant database were made with the two TIC data (samples)of all of lubricants. The rest of TIC data were sample (test). The HQI statistical technique was used for classification. The HQI values of samples were calculated from DB. For lubricant classification, when the criterion of identification was 0.95 of HQI value, the rate of matching was 91 %. And when the criterion of identification was 0.90 of HQI value, the rate of matching was 96 %.

For the past 6 years, repeated research was conducted to develop the NFS method which was to improve the current examination method to meet the needs in the domestic situations. This study analyzes validity and accuracy of the NFS method through carefully controlled experiments. Also, in order to compare the accuracy between the Utah technique - so far, it is the most popular technique used in domestic situationsand the newly developed NFS technique, same experimental conditions were applied. The lie group’s task was to do a virtual criminal act and then asked to lie about their virtual crime and the truth group’s task was to do a normal desk work. Once the participants were finished with their task, the polygraph examinations each employed the NFS technique and the Utah technique separately was administered. The NFS technique showed 90% sensitivity, 100% specificity with 94.4% accuracy among 18 people tested. 2 people out of 20 had to be dropped off due to indiscernibleness. And for the Utah technique, it showed 83.3% sensitivity, 100% specificity with 94.1% accuracy. Both techniques showed high levels of accuracy. Further implications and limitations regarding these techniques will be dealt on the discussion section.

In many case, large amount of female DNA mixed with small amount of male DNA in crime scene evidence. When we analyze Autosomal STR profile of those samples, we only get female STR profiles. However, if we analyze Y-STR profile, we can get male Y-STR profiles from that sample. We do not have any scientific explanation for that result. In this study, we want to find the male to female DNA mixture ratio that male Autosomal STR cannot be detected and also Y-STR can be detected even though male Autosomal STR is not detected. At first, we determine the amount of male DNA (63pg) that we can detect both male Autosomal STR and YSTR. After that, we add female DNA in various different ratios (1:0, 1:1, 1:5, 1:10, 1:10), than we compare each samples' Autosomal STR profiles. We can detect both male and female Autosomal STR form the sample that male to female DNA ratio is 1:5. We can notice the male Autosomal STR presence from ratio 1:10 samples, but we cannot get accurate male Autosomal STR profile. Above ratio 1:10, only female Autosomal STRs are detected from samples. We can also get accurate Y-STR profiles from ratio 1:2000 sample. We can get partial Y-STR profiles form ratio 1:4000 sample and above that, Y-STRs are not detected from samples. We collect and test samples from 50 cases that female Autosomal STR is detected however, only Y-STR is detected for male. From these cases, we find that we can detect Y-STR from ratio 1:460 and the amount of male DNA is 63pg.

In Korea, by imposing on ‘Acts on the protection and use of DNA identifying information’ from 2010, DNA profiles obtained from convicted offenders and crime scene evidence have been stored and managed at National forensic DNA database. This makes it possible to compare the unknown DNA profile from crime scene evidence to DNA profiles from convicted offenders in national forensic DNA database. If DNA profiles are matched, the crime cases will be solved by catching criminals. Therefore, confirming DNA profiles from crime scene evidence in DNA database to find match DNA profiles is one of the good ways reducing lots of time and money in order to solve crime cases. In this study, 5681 samples of theft scene removing such as murder, sexual assault, robbery were analyzed and classified into five parts which were 277 samples containing blood stain (4.9 %), 1998 samples containing saliva stain (35.2 %), 45 samples containing semen stain (0.8 %), 241 samples derived from human tissue (4.2 %), and 3120 touch samples (54.9 %). Interestingly, both saliva stain samples and touch samples were composed of about 80 percent of theft samples suggesting that two samples are important for solving theft casework. 97.5 percent of blood stain samples, 85.9 percent of saliva stain samples, 96.7 percent of semen stain samples, 56.3 percent of human-derived tissue samples, and 32.7 percent of touch samples were successfully STR typed. To know if DNA collection methods from theft samples have an effect on STR typing success, we divided 5681 samples into two groups. The first group was crime scene evidences directly collected from crime scenes, and the second group was DNA samples which was obtained from crime scene evidences using cotton swabs. Crime scene evidences account for 46.0 percent of theft samples, and DNA samples with cotton swab make up 54 percent of theft samples. On the contrary, 68.4 percent of crime scene evidences and 50.1 percent of DNA samples with cotton swab were successfully STR typed, respectively. These results suggest that development of DNA collecting method is required to increase success of STR typing. Touch samples including clothes, vehicle items, plugs and cables, stones, woods, steels, handled, or touched objects which typically containing low amounts of DNA have been more deeply investigated. Because touch samples are less exploited than other samples such as containing saliva, semen, or blood. As we expected, while touch samples showed the highest proportion among theft samples, STR typing success were the lowest among them suggesting that researches for increasing success of STR typing with touch samples are needed.

The traffic accidents by sudden vehicle start have been social concern in Korea. They are limited to the vehicles equipped with automatic transmission. We redefine the sudden unintended acceleration(malfunction of ECU and TCU in vehicle) as the state in which drivers cannot control rapid acceleration of vehicle because of the driving power exceeding the braking power by means of unidentified cause. We deal with 7 topics as follows : I. The recent investigation result about traffic accidents by sudden vehicle start, II. A statistical analysis on 40 Cases, III. Comparing 2 acceleration cable restraints with throttle valve's open trace case, IV. Comparing 4 undecidable cases, V. Proposing 6 methods for discriminating sudden unintended acceleration(malfunction) or driver's mal-operation, IV. Surveying foolproof and fail-safe function built in vehicle, VII. Reviewing SBS TV program critically. Ministry of Land, Infrastructure, and Transport in Korea did not present vehicle defects. In a statistical analysis, we classify 40 traffic accidents by 5 categories as follows : ①Sudden unintended acceleration(malfunction) ②Driver's mal-operation ③Acceleration cable restraints ④Undecidable case ⑤Impossible appraisement. The ratios of respective categories were 0 %, 80 %(32), 5 %(2), 10 %(4) and 5 %(2). The sudden unintended acceleration case was absent. The majority of cases were driver's mal-operation. They were identified by brake-stop lamp on/off images recorded in CCTV or blackbox. We propose 6 methods for discriminating sudden unintended acceleration or driver's maloperation as follows : ①Scuffmark-acceleration trace ②Throttle valve state ③Brake-stop lamp on/off images ④Brake-stop lamp bulb divided into hot shock and cold shock ⑤EDR(Event Data Recorder) ⑥Acceleration or brake pedal trace identified in shoes bottom. The brake-stop lamp on/off are mutually exclusive and are necessary and sufficient condition for deciding brake pedal on/off. They are most useful in discriminating sudden unintended acceleration or driver's mal-operation. There are several foolproof and failsafe functions in vehicle as follow : ①2 APS(Acceleration Position Sensor)s in engine ②Shift-lock in transmission ③ BOS(Brake Override System) in brake. We cannot identify a single brake-stop lamp- on image scene in reviewing SBS TV program.

The efficacy of forensic genotyping as an investigative tool has led to the continual expansion of national DNA databases as genotype profiles are added at an ever-increasing rate. To decrease the risk of false matches in the growing DNA databases, ENFSI and EDNAP recommended an extension of the European Standard Set (ESS) of loci. Following these recommendations, STR multiplexes have been developed by several commercial companies with the extended ESS of loci. AmplSTRⓇ NGM SElectTM PCR Amplification kit (Applied Biosystems) is the next generation kit contains amplify 10 loci plus the 5 new markers (D10S1248, D1S1656, D22S1045, D2S441, D12S391) recommended by ENFSI and EDNAP plus the highly discriminating SE33. With the aim of increasing STR markers of the missing children DNA databases in Korea we introduced new multiplex STR kit, AmplSTRⓇ NGM SElectTM kit (Applied Biosystems). In this study, we present the results of forensic validation studies with the NGM SElectTM kit including following aspects: reproducibility, sensitivity, performance on forensic samples, mixture sample analysis and kinship analysis. The NGM SElectTM kit showed comparable performances to the previously developed STR kits. NGM SElectTM kit showed improved performances, especially in regard to its sensitivity. Kinship analysis and forensic casework sample analysis result showed the NGM SElectTM kit are very informative for forensic purposes and the 6 additional loci provides a good tool for deficiency paternity cases.

When there was a car accident involving a motorcycle, it is crucial to determine the velocity before the collision. The sliding motorcycle after a collision finally come to a halt because of kinetic frictional force that exists between the moving objects and the roads. If we know the total sliding distance of a motorcycle we can calculate the speed just before the collision by a simple physical formula. For that we should know the sliding frictional coefficients of the motorcycle on the sliding surface. In this paper we inferred sliding frictional coefficients of motorcycles under various conditions by pulling it. As various sliding conditions, three kinds of sliding surfaces, two kinds of pulling velocities and two kinds of motorcycles are applied for comparison. By statistical analysis, it revealed that the frictional coefficients are highly dependent on all three factors including sliding surface, sliding velocity and motorcycle model. Hence the results should be carefully applied for accident investigations.

We investigated a fullerene-soot as a volatile-gas-absorber. Commercial gas- absorbers are expensive and some of them require a special instrument to desorber gas from absorbers. Also, none of them is useful to collect volatile-gases directly in the arson case. This study showed that fullerene-soot is somewhat better ignitable liquids adsorbent than carbon-strip (commonly used a commercial absorber). Toluene, hexane, undecane, gasoline, kerosene and diesel are used as test ignitable liquids. Fullerene-soot is a kind of charcoal material which has more than 7% fullerenes. Under our experiment condition with one compound, fullerene-soot gave at least 8 times higher intensity than charcoal-strip. Fullerene-soot was put in the prototype column for easy-handling. We collect ignitable liquid residues with a air-pump then fullerene-soot was heated and the headspace vapor was analysed by GC-FID. The results showed enough intense signals to verify materials without using any organic solvents to elute fullerene-soot. We think that fullrene-soot could be one of candidates to replace charcaol-strip and further modification makes a fullerene-soot column to apply in real arson case.

For the effective identification of drug-toxicants as the cause of death in forensic toxicology, it is important to analyze and establish the recent patterns of detected drugs in postmortem specimens and share their informations. So, we evaluated the results of the identification and their patterns of drug-toxicants detected in autopsy cases which occurred in Metropolitan areas including Seoul, Incheon and Gyeonggi province, and conducted by main office of National Forensic Service (NFS) during last three years (2010~2012). The results of requested cases in last three year, indicate that the frequencies of requests are 43.7 %, 43 % and 27 % from Gyeonggi, Seoul, and Incheon province, respectively. Men are more common than women, and positive results are less than negative results. As the detection rates of drug-toxicants, drugs, cyanide and pesticides are 93.27 %, 3.95 %, and 2.51 %, respectively. Most frequently detected drugs are chlorpheniramine (antihistamine), lidocaine(local anesthetics and antiarrhythmics) and atropine (parasympatholytics), which are supposed to be used for the emergent therapeutic purpose such as cardiac resuscitation in hospitals. Among pesticides, paraquat, methomyl, glyphosate, methidathion are highly detected in the order of frequency. These statistical analyses of drug-toxicants in postmortem specimens will be very helpful for prediction of causes of deaths in postmortem specimens.

Using universal and species-specific DNA markers, the identification of plant species from rice cake pastes (0.83gram) submitted as evidences in a fraud case was handled in this work. One universal species identification marker and rice-, wheat-, mulberry-, and mugwort-specific DNA markers were used for genetic identification of plant contents from rice cake pastes in powdered form. DNAs of submitted rice cake powder were purified with QIAGEN DNeasy Plant Mini Kit and amplified with primer pairs of each genetic region. The acquired sequences of universal trnL-trnF intergenic spacer (IGS) from evidence were compared with DNA databases in National Center for Biotechnology Information (NCBI) and so they were identical to the ramie sequences. Also, we tried to identify the plant constituent parts of evidence using a presence/absence test of each species-specific marker. The rice RM171 marker and sequence characterized amplified regions (SCAR) marker of mugwort showed specific amplicons from evidence’s DNA, but waxy marker of wheat and chalcone isomerase marker of mulberry did not. According to these analysis results, the plant contents of rice cake powder were rice, ramie, and mugwort. The powder did not contain wheat and mulberry.

In this study, we identified DNA profiles of tree related 12 residues found at the crime scene and the suspected 89 trees in the farm by microsatellites analysis of tetranucleotide repeat motif at B4630 and B4637 loci. As a result, we observed 9 kinds of DNA profiles in 12 evidences of the crime scene and 75 kinds of DNA profiles in 89 evidences of the farm. Significantly, evidence No. 2 and No. 8 of crime scene matched with evidence No. 75 of the farm in B4630 176 bp and B4637 323 bp. Evidence No. 4 of crime scene matched with evidence No. 69, 77, 84 of the farm in B4630 176 bp and B4637 327 bp, 335 bp. Evidence No. 5 and No. 11 of crime scene matched with evidence No. 22, 57, 82 of the farm in B4630 150 bp, 158 bp and B4637 323 bp, 327 bp. Evidence No. 9 of crime scene matched with evidence No. 37, 40, 63 of the farm in B4630 146 bp, 150 bp, 158 bp and B4637 323 bp, 335 bp. As a consequence, we observed 1~3 pattern of allele in B4630 loci and 1~2 pattern of allele in B4637 loci of every evidence. And almost every allele showed tetranucleotide repeat motif. In conclusion, the research of many more kinds of microsatellite and multiplex PCR needs in the future and as the result we can prepare legal evidence with speed and accuracy against the future coming soon.

The purpose of case application reports was to test the potential utilities in forensic science (DNA analysis) and criminal investigative analysis (geographical and/or behavioural profiling approach) for capturing felonious criminals. In order to determine whether a series of unsolved crimes has been committed by a certain offender, the police often must rely on analyses of several scientific investigative methods included the reliable evidence gathering as well as the traditional DNA profile searching. While established procedures provide the meaningful conclusion, the practical problems with economic cost for investigation and the use of small-size DNA profile database are that these methods may be unavailable and insufficient for solving criminal cases. So we develop a comprehensive system including the close biological relatives (sibling and patrilineal) for indirect comparison using the autosomal and/or the Y chromosomal STRs for helping the forensic case analysts. Across a range of conditions, the application system demonstrates efficient investigative tool to pursue unknown offenders. Potential explanations for the results are provided, implications are discussed, and future research directions are presented.

We report a case on the comprehensive application of forensic science and criminal profiling for capturing a serial rapist. Since June 2001 a rapist from Chungnam Province (the west coast area) committed at least 8 rapes. The frequency of the CODIS core STR profile identified was estimated to be 4.44 x 10-18. Crime scene aspects of a serial rapist show similar components in the viewpoint of geographical and behavioural characteristics. 17 Y-STR haplotype of the biological materials left at eight serial crime scenes was carried a star-like cluster from a specific surname in Korea population data [Forensic Sci. Int.: Genetics 5(2011), e122- 123]. In societies, patrilineal surnames and Y-STR haplotypes are expected to be correlated. This characteristic could help defining an initial pool of suspects in forensic routine by the analysis of biological material left at the crime scene and evaluating the haplotype correlated. It was expected as a suspect with common surname living the west coast area of Chungcheong district by the application of efficient methods. We suggest the comprehensive application including forensic DNA analysis and criminal profiling could lead to trace felonious criminals in forensic investigations on a much wider scale than has been used to date.

MMS is a kind of private remedy and an abbreviated word for Miracle mineral supplements. A person who had no medical licence insisted the dead who died by pneumonia on using this MMS and sauna in a hot and cold bath. So-called MMS remedy was made up of active liquid and base liquid. In that remedy, a drop of each solution was added to drinking water. The traveling healer also insisted that the patient had to drink it twice a day till he might be cured and didn’t use any medicine. By using the MMS remedy, the condition of the patient became worse and he suffered from constipation. The charlatan gave him another powder for constipation but that powder made him diarrhea. After all, he was dead by dehydration because of a complication with diarrhea, poor health and pneumonia. The evidences submitted to us were MMS solution and the powder. We reported that what were the components and what was the problem in this paper.

5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), commonly called Foxy or Foxy methoxy is one of the novel synthetic designer drugs derived from tryptamine. It has hallucinogenic properties similar to other tryptamines, euphoria, empathy, a sense of intimacy to others, and emotional distress. It also causes dilated pupils, visual and auditory distortion, nausea, vomiting and diarrhea in its abusers. 5-MeO-DIPT has been abused since the 1990s. Due to its recreational abuse, many countries including several European countries, Japan and USA have banned the use of this drug since 1999. Korea Government started the control of 5-MeO-DIPT since 2006. Even though there were a few cases of its identification in seized tablets in Korea, there was no case of 5-MeO-DIPT user. Recently, we encountered two male abusers who took a pill contained 5-MeO-DIPT which was bought from Japan. From their urine samples, we confirmed 5-Meo-DIPT and its metabolites, 5-hydroxy-N,N-diisopropyltryptamine (5-OH-DIPT), 6-hydroxy-5- methoxy?N,N-diisopropyl tryptamine (6-OH-5-MeO-DIPT), 5-methoxy- N-isopropyltryptamine (5-MeO-NIPT). In order to identify 5- MeO-DIPT and its metabolites, the urine specimens were extracted in Automatic Solid-phased extraction with a mixed-mode cation exchange cartridge. For identification, they were derivatized by MSTFA and analyzed by using Gas chromatography/mass spectrometry with full scan mode. As a result, we confirmed 5-MeO-DIPT and its metabolites, 5-OH-DIPT, 6-OH-5-MeO -DIPT, 5-MeO-NIPT in the two abusers’urine. It was the first case that was detected 5-MeO-DIPT and its metabolites from abusers’urine in Korea.

Early in the summer, A carbon monoxide poisoning accident occurred inside the car that was stopped on the shoulder of the road. The windows were closed and the air conditioning was turned on. All five passengers was unconscious. Their blood carbon monoxide-hemoglobin(CO-Hb) content was 31.0 %~ 39.5 % range. If they were a little more exposure to carbon monoxide, All of them would have died. The carbon monoxide concentrations were measured in the indoor 0.073 % and in the trunk 0.136 %. The concentration was higher in the trunk than indoor. The exhaust gas pipe was bent to the inside of the rear bumper due to an accident. The car's exhaust gases does not spread into the air, and spread to the inside of bumper. The air passage in the trunk is damaged, the exhaust gas flow in easily, and spread into the indoor.