How important are interview methods and questionnaire designs in research on self-reported juvenile delinquency? An experimental comparison of Internet vs paper-and-pencil questionnaires and different definitions of the reference period

There has been relatively little change over recent decades in the methods used in research on self-reported delinquency. Face-to-face interviews and self-administered interviews in the classroom are still the predominant alternatives envisaged. New methods have been brought into the picture by recent computer technology, the Internet, and an increasing availability of computer equipment and Internet access in schools. In the autumn of 2004, a controlled experiment was conducted with 1,203 students in Lausanne (Switzerland), where “paper-and-pencil” questionnaires were compared with computer-assisted interviews through the Internet. The experiment included a test of two different definitions of the (same) reference period. After the introductory question (“Did you ever...”), students were asked how many times they had done it (or experienced it), if ever, “over the last 12 months” or “since the October 2003 vacation”. Few significant differences were found between the results obtained by the two methods and for the two definitions of the reference period, in the answers concerning victimisation, self-reported delinquency, drug use, failure to respond (missing data). Students were found to be more motivated to respond through the Internet, take less time for filling out the questionnaire, and were apparently more confident of privacy, while the school principals were less reluctant to allow classes to be interviewed through the Internet. The Internet method also involves considerable cost reductions, which is a critical advantage if self-reported delinquency surveys are to become a routinely applied method of evaluation, particularly so in countries with limited resources. On balance, the Internet may be instrumental in making research on self-reported delinquency far more feasible in situations where limited resources so far have prevented its implementation.

Heat Induced Changes to Dental Resin Composites: A Reference in Forensic Investigations?*

The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses.     

A study to narrow down the time when a hyoid bone fracture was sustained

An unstable hyoid bone that can be loosely moved during autopsy is initial reason to suspect trauma to the neck. The question to be answered is whether the increased mobility is due to incomplete ossification of the hyoid, a postmortem injury (damage), or an ante-mortem injury, possibly related to the cause of death. This is the first study to systematically assess whether stereomicroscopic examinations and flat-panel CT-scans of isolated, unstable hyoid bones can add information to the macroscopic examination by helping to determine when the instability arose. Sixteen isolated hyoid bones (8 female, 8 male; 4-87 years-old) were examined after being macerated. Four of the hyoid bones were already classified as unstable during autopsy. Of the other 12, 7 were fractured immediately after autopsy before being macerated, and 5 were fractured after being macerated. There were, in total, six different diagnostic constellations. Stereo-microscopic examination did not yield additional information compared with the macroscopic examination. Flat-panel CT allowed distinction between an incomplete ossification of the hyoid and a fracture, but did not help in determining whether the fracture had been sustained peri- or postmortem.     

Ossification Degrees of Cranial Sutures Determined with Flat‐Panel Computed Tomography: Narrowing the Age Estimate with Extrema

Abstract: Since Broca’s time (1824–1880), ossification of the neurocranial sutures has been used as a characteristic of age. Current approaches include the visual macroscopic examination of ecto and endocranial sutures. The evaluation of the cross‐section of sutures usually necessitates the destruction of the neurocranium. In a nondestructive alternative approach that was tested within the context of the “Digital Forensic Osteology” project that ran in cooperation with the Virtopsy^®‐Project, it emerged that the resolution of conventional multi‐slice computed tomography data sets was not high enough to image sutures. Thus for the experiments presented here, the eXplore Locus Ultra flat‐panel computed tomography scanner from GE Healthcare was used. Calottes were scanned during autopsy and then immediately returned to the corpse. So far, the skullcaps of 221 individuals have been scanned. The cross‐sections of 14 suture segments could be assessed for seven previously defined stages of ossification. In a converse step, the 14 highest and lowest age estimate values corresponding to the individual stages of suture closure found were estimated for each calotte. The obtained ranges narrowing down the age estimate were evaluated with statistics. A mean value of 43.31 years for the range of narrowed age estimates shows that this method can be a useful aid in estimating age. The results of intra‐ and inter‐observer tests showed good overall agreement between the findings of three observers. This method is suitable for a nondestructive age estimation and can be used for the entire calotte.     

Speech Watermarking: An Approach for the Forensic Analysis of Digital Telephonic Recordings*

Abstract: In this article, the authors discuss the problem of forensic authentication of digital audio recordings. Although forensic audio has been addressed in several articles, the existing approaches are focused on analog magnetic recordings, which are less prevalent because of the large amount of digital recorders available on the market (optical, solid state, hard disks, etc.). An approach based on digital signal processing that consists of spread spectrum techniques for speech watermarking is presented. This approach presents the advantage that the authentication is based on the signal itself rather than the recording format. Thus, it is valid for usual recording devices in police‐controlled telephone intercepts. In addition, our proposal allows for the introduction of relevant information such as the recording date and time and all the relevant data (this is not always possible with classical systems). Our experimental results reveal that the speech watermarking procedure does not interfere in a significant way with the posterior forensic speaker identification.     

Cleaning up your act: Forensic awareness as a detection avoidance strategy

Purpose

Although rational choice researchers has investigated how offenders successfully commit certain crimes, there is a lack of research looking at the factors explaining the use - or not - of certain detection avoidance strategies. This study introduces the concept of “forensic awareness” as a detection avoidance strategy, and proposes to examine the effect of disinhibitors, target selection behaviors, and acts that may potentially leave evidence at the crime scene on its use.

Methods

Factors influencing forensic awareness are tested using logistic regression models on a sample of 222 rape events collected from offenders incarcerated in Canada.

Results

Offenders exhibit less forensic awareness when under the influence of drugs and/or alcohol. However, offenders who show some form of target selection are more likely to take forensic precautions. Finally, offenders who break and enter in the victim's residence, and undertake specific sexual acts during the crime are also more likely to exhibit forensic awareness.

Conclusion

Despite the increasing use and knowledge of forensic evidence by law enforcement, offenders are inconsistent in their forensic awareness and they direct most of their efforts toward protecting their identity, neglecting to either destroy or clean up DNA that could be recovered at the crime scene.     

Kein Aussonderungsrecht am Kaufpreis im Konkurs des Verkäufers aufgrund der Nebenabrede, den Kaufpreis für den Fall der Ausübung eines Rückverkaufsrechts "treuhändig" zu halten

Eine Vereinbarung, derzufolge die Verk?ufer nach wirksamer übertragung des verkauften Gesch?ftsanteils an einer GmbH den dafür gezahlten Kaufpreis für den Fall der Ausübung eines Rückverkaufsrechts des K?ufers "treuh?ndig" für den K?ufer halten und dabei das wirtschaftliche Risiko (etwa einer verlustbringenden Veranlagung) tragen sollen, gew?hrt dem K?ufer im Konkurs der Verk?ufer kein Aussonderungsrecht. Durch die Geltendmachung des Rückverkaufsrechts im Sinn des § 1071 ABGB entsteht lediglich ein schuldrechtlicher Anspruch auf übertragung des (im Voraus festgelegten) Rückkaufpreises gegen Rückübertragung der Gesellschaftsanteile. Die dargestellte Nebenabrede der Parteien rechtfertigt es nicht, die Forderungen gegen die Bank als den Verk?ufern wirtschaftlich fremdes Verm?gen anzusehen; sie kann daher keinen Aussonderungsgrund bilden.     

Gentechnik im Saatgut – ein wiederkehrendes Problem

Die Europ?ische Union und die Bundesrepublik Deutschland sind hinsichtlich des Anbaus gentechnisch ver?nderter Organismen (GVO) sehr zurückhaltend, w?hrend au?erhalb Europas die Zahl der angebauten gentechnisch ver?nderten Kulturpflanzen stetig zunimmt. Die Anwesenheit von GVO, die nicht zum Anbau zugelassen sind, in Saatgut ist deshalb ein wiederkehrendes Problem mit wachsender Bedeutung. Der Beitrag analysiert die dazu vorliegende Rechtsprechung der Verwaltungsgerichte und demonstriert am jüngsten Fall der Saatgutkontamination (NK603-Spuren in Maissaatgut) die Anwendung des differenzierten Regelungssystems des GenTG, das den Vollzugsbeh?rden anspruchsvolle Ermittlungsund Abw?gungspflichten auferlegt.