Search

Continuous probabilistic genotyping (PG) systems are becoming the default method for calculating likelihood ratios (LRs) for competing propositions about DNA mixtures. Calculation of the LR relies on numerical methods and simultaneous probabilistic simulations of multiple variables rather than on analytical solutions alone. Some also require modelling of individual laboratory processes that give rise to electropherogram artefacts and peak height variance. For these reasons, it has been argued that any LR produced by continuous PG is unique and cannot be compared with another. We challenge this assumption and demonstrate that there are a set of conditions defining specific DNA mixtures which can produce an aspirational LR and thereby provide a measure of reproducibility for DNA profiling systems incorporating PG. Such DNA mixtures could serve as the basis for inter-laboratory comparisons, even when different STR amplification kits are employed. We propose a procedure for an inter-laboratory comparison consistent with these conditions.

Unrecovered War Casualties – Army (UWC-A) is part of the Australian Defence Force (ADF) and investigates unaccounted for Australian soldiers from previous conflicts. In the Asia-Pacific region of W...

Tetrahydrocannabinol (THC), the principal psychoactive constituent of Cannabis, and other cannabinoids can be transferred onto surfaces by direct or secondary contact. Identification of these trace...

The differentiation between bloodstain patterns resulting from impact events and those from the expiration of blood can be crucial to crime scene reconstruction. Physical characteristics used to di...

The ability to accurately detect bloodstains is fundamental to crime scene examination; however, traditional methods can be inadequate for use on many dark-coloured surfaces commonly encountered at...

DNA has played a revolutionary role within criminal justice systems across the world. This paper, while honouring the role DNA evidence has played, nevertheless aims to set out (in plain English in order to make it readily accessible to lawyers dealing with this evidence) some on-going and new key aspects related to the use of DNA evidence in the courtroom. Areas canvassed relate to identification evidence, activity level evidence and DNA mixtures. Specific issues considered include the potential for misunderstanding of DNA statistics both generally and when ‘partial’ match profiles are involved; concerns in regard to underlying assumptions and interpretation of transfer and activity information to determine how and when the DNA was deposited; and a highlighting of a change to the way statistical calculations are made through new software being used across Australia and internationally, including ‘black box’ assumptions that go into those calculations that is particularly relevant to DNA mixtures. This article is Australian-based and some key Australian cases relevant to these issues are considered, however the issues and principles contained within the article are widely applicable within an international context.

Estimates of mutation rates for various regions of the mitochondrial genome (mtGenome) vary widely, depending on whether they are inferred using a phylogenetic approach or obtained directly from pedigrees. Traditionally, only the control region, or small portions of the coding region have been targeted for analysis due to the cost and effort required to produce whole mtGenome Sanger profiles. Here, we report one of the first pedigree derived mutation rates for the entire human mtGenome. The entire mtGenome from 225 individuals originating from Norfolk Island was analysed to estimate the population mutation rate and compared against published mutation rates. These individuals were from 45 maternal lineages spanning 345 generational events. Mutation rates for various portions of the mtGenome were calculated. Nine mutations (including two transitions and seven cases of heteroplasmy) were observed, resulting in a rate of 0.063 mutations/site/million years (95% confidence interval: 0.033 – 0.118). These mutation rates are approximately 17 times higher than estimates derived from phylogenetic analysis with heteroplasmy detected in 13 samples (n=225, 5.8% individuals). Providing one of the first pedigree derived estimates for the entire mtGenome, this study provides a better understanding of mtGenome evolution and has relevance to many research fields, including medicine, anthropology and forensics.

Dear Editor A recent publication [1] has claimed to address criticism of probabilistic genotyping by the President’s Council of Advisors on Science and Technology (PCAST) report [2] and addendum [3]. PCAST considered probabilistic genotyping to have “foundational validity … under limited circumstances (specifically, a three-person mixture in which the minor contributor constitutes at least 20 percent of the DNA in the mixture), but that substantially more evidence is needed to establish foundational validity across broader settings” [2]. For more than three contributors and/or for mixtures with minor contributors constituting less than 20% of the DNA, PCAST recommends “the creation and dissemination … of large collections of hundreds of DNA profiles created from known mixtures” [2]. Bright et al. [1] draw upon guidelines for testing reliability and validity of probabilistic genotyping published by The Scientific Working Group on DNA Analysis Methods (SWGDAM) [4] and the International Society for Forensic Genetics (ISFG) [5] to produce an internal validation of continuous probabilistic genotyping using STRmix™ on electropherogram (epg) outputs provided by multiple laboratories. Their study extends an internal validation performed only in the FBI Laboratory at Quantico, Virginia (USA) [6]. We believe that the publication by Bright et al. [1] is a valuable first step in the direction of establishing a foundational validity for mixture interpretation using probabilistic software, as recommended by the PCAST report. We hope that our suggestions would help to better address this issue.

Bloodstain pattern analysis (BPA) has long been accepted by courts as an area of expertise; however, that position has recently been challenged. The discipline has been criticized for limited empirical research into practitioner determination error rates and whether determinations require specialized knowledge/expertise, including whether practitioner experience level influences accuracy. This study attempted to address these knowledge gaps as they relate to bloodstain pattern recognition. The aims were twofold: to establish whether practitioners would outperform lay non-practitioners, and whether practitioner experience influenced accuracy and error in determinations. Comparisons of practitioner responses under three scenarios (forced, casework, and definitive) were also made to assess conservatism/certainty in pattern recognition. Participants (both BPA practitioners and non-practitioners) analyzed photographs of bloodstain patterns and made determinations of the broad bloodstain category and specific bloodstain pattern type. When forced to provide only a single response, practitioners identified bloodstain categories and patterns significantly more accurately than non-practitioners (p = 0.0001, p

Footwear impressions are a common form of evidence found at crime scenes, and the accurate recovery and recording of such impressions is critical for shoe sole comparison and identification. The lifting of shoe sole impressions from hot surfaces (>30°C/86°F) and in hot environments has received little attention in the literature, particularly in relation to the recovery of class and randomly acquired characteristics (RACs) required for accurate comparisons. This study addressed this knowledge gap by comparing the performance of three common impression lifters (gelatin, adhesive, and vinyl static cling film) at recovering shoe sole impressions in dust from hot flooring substrates. Dry origin dust shoe sole impressions were made on ceramic tile, galvanized metal, and laminated wood flooring using a shoe that possessed two RACs and five class characteristics present on the sole. Substrates were left in direct full sun for five hours during a summer day prior to lifting. Performance was measured by the proportion of RACs and class characteristics visible in each lifted impression. Results demonstrated that the vinyl static cling film tested performed poorly across all substrates, particularly for metal (23.8% marks recovered), including notable shrinkage of the lifted impression. In contrast, adhesive (~96% marks recovered over all substrates), and to a lesser extent gelatin (~85%), lifts were highly successful on hot substrates. These data suggest that adhesive lifts can consistently and accurately recover shoe sole impressions from hot substrates. This study contributes critical information for crime scene examiners to improve and expand evidence recovery in hot environments.

Many deployable forensic capabilities, including those used by the Australian Defense Force (ADF), employ mobile battery-operated fridge/freezers for DNA sample preservation that are not suitable for rapid response application due to their size and weight. These fridge/freezers are expensive, require regular specialised maintenance, and have a set payload. A variety of transport media are successful preservatives for DNA samples, however, there is no research specifically targeted to their suitability for operational environments where temperatures exceed 50 °C. This research examined whether sodium chloride (NaCl), ethanol, and dimethyl sulfoxide (DMSO) could preserve muscle and bone samples (fresh and early decomposition) as effectively as refrigeration, when stored at 21 °C, 45 °C, 55 °C, and 65 °C for at least one week. A total of 78 muscle and 78 bone samples were collected from an unknown deceased individual. Half of each tissue type was stored at 30 °C for 48 h to induce early decomposition. Following this, samples were stored in the transport media for one week at the above temperatures, and a control set of samples were refrigerated (−4 °C) without any transport media. Preserved samples would need to provide DNA profiles comparable to the refrigerated samples for the transport media to be considered a successful replacement method. NaCl and 70% ethanol preserved muscle samples (fresh and decomposed) up to 65 °C, as well as 70% ethanol and 20% DMSO for fresh bone samples. These results were comparable with refrigeration and therefore, these preservatives could be used in rapid response operations by the military and for disaster victim identification. Conversely, under the conditions of this study, 20% DMSO and 70% ethanol failed to consistently produce full DNA profiles from decomposed bone, and NaCl performed poorly at preserving DNA from fresh and decomposed bone samples.

Purpose The purpose of this paper is to reveal difficulties associated with identifying child victims of the 2004 South-East Asia Tsunami at the Thai Tsunami Victim Identification (TTVI) operation in Phuket and explores two strategies that increased child identifications. Design/methodology/approach Data allowing comparison of identification proportions between adult and child (defined as ⩽16 years old) victims of six nationalities and the forensic methods used to establish identification were used in this study. Findings The first 100 days of the operation revealed that the proportion of adult identifications far outweighed the proportion of child identifications. Moreover, the younger the child, the longer the identification process took (p Originality/value The implementation of these two strategies at the TTVI helped to overcome initial complexities, namely, the lack of ante-mortem and PM material, and increased child identifications.

Detection of blood on dark materials is difficult for crime scene examiners so presumptive tests are used to assist. This study compared the ability of luminol, leuko crystal violet, tetramethylbenzidine, and Combur Test E to detect whole, diluted blood (1:100) and a key-shaped blood transfer stain (1:10), on dark cotton sheeting, tea towel, socks, synthetic carpet, and car mats. Powdered bleach was used to evaluate specificity of the blood detection tests. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall misclassification rate (OMR) assessed the quality of the blood tests. Luminol was the preferred test for diluted blood having the highest sensitivity (79%–96%), NPV (66%–93%), and the lowest OMR (3%–15%). Luminol was also found to be most efficient with a testing time on 25 items of 2 h 50 min compared with up to 8 h. Overall, luminol was the most effective method, also providing information on bloodstain patterns.

Mitochondrial DNA (mtDNA) is used for identification of Australian military personnel whose remains are recovered from historical conflicts. A mtDNA sample database does not exist for Australian soldiers that served in World War I (WWI), World War II (WWII) and the Korean War, meaning it is unknown what common haplotypes may have existed among these soldiers, risking identification errors. Haplotype diversity (position 16,024 to 548) was examined in a sample of 254 unrelated WWII-era European-Australians. Of these, 220 different haplotypes were observed, and it is estimated that between 18% and 29% of Australian soldiers who served in historical conflicts have common haplotypes (95% CI). This research demonstrates that mtDNA control region analysis of historical military remains will provide a lower than expected power of discrimination given the population structure of the time, and enlistment policies targeting Australians of European decent. The point estimates for 52% of the common haplotypes obtained in the historical European-Australian sample were not represented in the confidence intervals for European and Western-European EMPOP data. Creation of targeted sample data reflecting correct ancestry of the WWI and II soldiers and additional mtDNA and Y-STR analysis are essential to avoid misidentification of Australian soldiers from historical conflicts.

The Thai Tsunami Victim Identification operation was the largest disaster victim identification operation in history, involving 3,679 unidentified victims from 41 countries, and police and forensic scientists from over 30 countries. This paper evaluates the DNA response to the 26 December 2004 South-East Asia Tsunami, measuring its impact at different stages of the operation. Only 15 identifications were established using DNA during the first 5 months, compared to 307 by fingerprints, 1,266 by dental, and 11 by physical analysis. Critical obstacles, such as available ante-mortem and post-mortem DNA profiles, data management challenges, and automated DNA matching issues were impeding the DNA response. Recognizing and resolving the key issues hindering DNA identification resulted in increased DNA identifications during the middle and late stages of the operation.Consideration of victim demographics was crucial to understanding the impact of different identification methods during the operation. DNA ...

The three-compartment (3-C) model of physique assessment (fat mass, fat-free mass, water) incorporates total body water (TBW) whereas the two-compartment model (2-C) assumes a TBW of 73.72%. Deuterium dilution (D2O) is the reference method for measuring TBW but is expensive and time consuming. Multifrequency bioelectrical impedance spectroscopy (BIS SFB7) estimates TBW instantaneously and claims high precision. Our aim was to compare SFB7 with D2O for estimating TBW in resistance trained males (BMI >25kg/m2). We included TBWBIS estimates in a 3-C model and contrasted this and the 2-C model against the reference 3-C model using TBWD2O. TBW of 29 males (32.4 ± 8.5 years; 183.4 ± 7.2 cm; 92.5 ± 9.9 kg; 27.5 ± 2.6 kg/m2) was measured using SFB7 and D2O. Body density was measured by BODPOD, with body composition calculated using the Siri equation. TBWBIS values were consistent with TBWD2O (SEE = 2.65L; TE = 2.6L) as were %BF values from the 3-C model (BODPOD + TBWBIS) with the 3-C reference model (SEE = 2.20%; TE = 2.20%). For subjects with TBW more than 1% from the assumed 73.72% (n = 16), %BF from the 2-C model differed significantly from the reference 3-C model (Slope 0.6888; Intercept 5.093). The BIS SFB7 measured TBW accurately compared with D2O. The 2C model with an assumed TBW of 73.72% introduces error in the estimation of body composition. We recommend TBW should be measured, either via the traditional D2O method or when resources are limited, with BIS, so that body composition estimates are enhanced. The BIS can be accurately used in 3C equations to better predict TBW and BF% in resistance trained males compared with a 2C model.

The declining condition of river systems associated with rapid development of human societies has led to substantial declines in fish diversity. One cause of decline is the loss of in-stream Structural Woody Habitat (SWH), an important component of stream ecosystems, particularly as fish habitat. As a result there has been an increase in the number of rehabilitation programs that introduce SWH into rivers. This paper assesses fish responses to SWH introduction in riffles and pools in the Hunter River, eastern Australia, using a Multiple-Before-After-Control-Impact (MBACI) experimental and analytical design. In the riffle experiment, species richness was comparable among all control and treatment riffles across the entire study period. However, there were significant differences in assemblage structure, fish abundance, and biomass between control and treated riffles. The introduction of SWH (bank embedded deflector jams) appeared to create additional habitat which was utilized by one native fish species (Retropinna semoni-Australian smelt) and one alien species (Gambusia holbrooki-mosquito fish). In pools there were no significant changes in fish species richness, abundance, or biomass following introduction of SWH (pool jams). These findings have important practical and cost implications in terms of the design and implementation of rehabilitation strategies using SWH to restore fish assemblages in degraded streams.

Land use/cover and mangrove spatial changes were assessed for ten sites and their sub-catchments in Southeast Queensland, Australia. Two time periods were involved: 1972-1990, a period of relatively high rainfall, and 1990-2004, which was significantly drier. Aerial photographs and Landsat satellite imagery were used to map the inter-tidal wetlands and classify the land use/cover in the sub-catchments. A Maximum Likelihood Classification was used to map three types of land cover: agriculture, built-up and plantation forest. Mangroves (mainly Avicennia marina) were the focus as they have been recorded over recent decades encroaching into salt marsh. The Mangrove-Salt marsh Interface (MSI) Index was developed to quantify the relative opportunity for mangroves to expand into salt marshes, based on the shared boundary between them. The index showed a consistent relationship with mangrove expansion and change. To address problems of high dimensionality and multi-collinearity of predictor variables, a Partial Least Squares Regression (PLSR) model was used. A key finding of this research was that the contribution of environmental variables to spatial changes in the mangroves was altered following a reduction in rainfall. For example, agriculture had more influence on mangrove expansion and change during the wet period than during the dry period.

Changes in rainfall pattern have been suggested as a mechanism for the landward incursion of mangrove into salt marsh. The aim of the research was to assess the relationship between rainfall patterns and the spatial distribution of mangrove forests at study sites in Moreton Bay, Southeast Queensland, Australia, over a 32-year period from 1972 to 2004. To identify periods of relatively consistent rainfall patterns points at which rainfall patterns changed (change-points) were identified using the non-parametric Pettitt–Mann–Whitney-Statistic and the cumulative sum technique. The change-points were then used to define the temporal periods over which changes to mangrove area were assessed. Both mangrove and salt marsh area were measured by digitizing aerial photographs acquired in 1972, 1990 (the year with the most significant change-point), and 2004. The rates of change in mangrove area pre-1990 (a wetter period) and post-1990 (a drier period) were estimated. A significant positive relationship was demonstrated between rainfall variables and landward mangrove expansion, but not for seaward expansion. We concluded that rainfall variability is one of the principal factors influencing the rate of upslope encroachment of mangrove. However, the rate of expansion may vary from site to site due to site-specific geomorphological and hydrological characteristics and the level of disturbance in the catchment.

Simulated ecological datasets have been widely used to assess the ability of ordination techniques to portray patterns in ecological assemblage data. Such datasets typically contain a single assemblage sampled over an environmental gradient or set of gradients. Little has been done on the generation of artificial datasets that contain a number of different species assemblages, to aid in the evaluation of multivariate techniques that test for differences between assemblages of species. This paper describes and compares two simulation methods that generate ecologically realistic artificial multi-assemblage datasets. Both methods provide multivariate data (e.g. species abundances) for replicate sites within discretely different assemblages. The first technique is a coenocline model based on species' responses to variation modeled by a five-parameter β-function, where variation in species abundances both within and between assemblages is governed by differences in the positions of sites and assemblages along environmental gradients. The second technique, the resampling method, involves bootstrap resampling of real assemblage datasets, with the addition of selected types of controlled differences between assemblages. Here we use it to generate turnover in species composition. We calibrate both simulation methods based on a field assemblage of bird species. The two different simulation methods portray different levels and types of between-assemblage variation. The resampling method allows greater control over some aspects of assemblage difference (e.g. independently varying differences in species richness and compositional turnover) than the coenocline method. Both can generate usable replicated simulated datasets for assessing the ability of multivariate tests to detect ecological variation among assemblages.

The international disaster victim identification (DVI) response to the Boxing Day tsunami, led by the Royal Thai Police in Phuket, Thailand, was one of the largest and most complex in DVI history. Referred to as the Thai Tsunami Victim Identification operation, the group comprised a multi-national, multi-agency, and multi-disciplinary team. The traditional DVI approach proved successful in identifying a large number of victims quickly. However, the team struggled to identify certain victims due to incomplete or poor quality ante-mortem and post-mortem data. In response to these challenges, a new 'near-threshold' DVI management strategy was implemented to target presumptive identifications and improve operational efficiency. The strategy was implemented by the DNA Team, therefore DNA kinship matches that just failed to reach the reporting threshold of 99.9% were prioritized, however the same approach could be taken by targeting, for example, cases with partial fingerprint matches. The presumptive DNA identifications were progressively filtered through the Investigation, Dental and Fingerprint Teams to add additional information necessary to either strengthen or conclusively exclude the identification. Over a five-month period 111 victims from ten countries were identified using this targeted approach. The new identifications comprised 87 adults, 24 children and included 97 Thai locals. New data from the Fingerprint Team established nearly 60% of the total near-threshold identifications and the combined DNA/Physical method was responsible for over 30%. Implementing the new strategy, targeting near-threshold cases, had positive management implications. The process initiated additional ante-mortem information collections, and established a much-needed, distinct "end-point" for unresolved cases.

This paper explores one aspect of spatial dependence for the offence of burglary, utilising epidemiological methods for the study of infectious diseases to investigate the phenomenon of near repeat victimization. The near repeat burglary hypothesis states that proximity to a burgled dwelling increases burglary risk for those areas that have a high degree of housing homogeneity and that this risk is similar in nature to the temporarily heightened risk of becoming a repeat victim after an initial victimization. The near repeat hypothesis was tested on 34 months of police recorded burglary data across a high crime area of Brisbane, Australia. Near repeats were shown to exist in the study area, mainly in suburbs containing homogeneous housing. Little or no housing diversity, in terms of the type of physical construction and general appearance of dwellings, serves to restrict the extent of repeat victimization. Housing diversity allows offenders a choice of targets, and favoured targets will be 'revisited' by burglars. Near identical targets usually present no motive for an offender to favour one property over another. Thus in areas with low housing diversity, victim prevalence should be higher than in areas with heterogeneous housing.

A study of analytes for ground water monitoring was conducted at 10 municipal solid waste landfills in northern New South Wales (NSW), Australia. From literature review, analytes were proposed and then approved by the NSW Environment Protection Authority (EPA) for initial ground water and leachate monitoring. Eight rounds of initial baseline monitoring using traditional geochemical analytes were conducted in uncontaminated ground water at a new, lined landfill. Four rounds of initial assessment monitoring were conducted at nine unlined or only partially lined old landfills. Analytes for the old landfills were selected with a health risk emphasis because ground water may already be contaminated. At the old landfill sites, analytes with values indicating contamination were often limited to one particular analytical group, although the analytical group represented differed from site to site. As a result, the most environmentally responsible suite of analytes for baseline monitoring is the traditional geochemical approach; free carbon dioxide for landfill gas; and organics in the form of volatile organic compounds for old landfills, but benzene, toluene, ethylbenzene, and xylene when wells are close to a new landfill. The current Subtitle D (U.S. EPA 1991) analytes proved inadequate. They would not have detected the majority of contaminants or contaminant indicators at the old landfills, i.e., organic nitrogen, ammonia, nitrate, iron, and manganese. After completion of initial monitoring at each site, reduced lists of analytes for ongoing monitoring were proposed and approved by the NSW EPA. The lists were based on literature evidence, contaminants, and contaminant indicators found in ground water at the old landfills, and in some cases leachate versus ground water concentrations. For the new landfill, the principle of limited analytes representing a broad range of analytical groups was used to assure precautionary environmental outcomes. At present-day costs, cost savings for analyses alone at the new landfill are AD251, 160 over the 70-year life of the landfill.

This study concerns the problem of pump position in landfill monitoring wells and the correct time to stop purging and start sampling. Literature purge volume determination methods fail to use sufficient analyte values for comprehensive study of the stabilization plateau. From field studies it is recommended that prior to commencement of a sampling program a purge study be undertaken to determine pump position and optimum purge volume by conducting (1) a preliminary vertical electrical conductivity (EC) profile: (2) vertical profiling of formation water EC values by low-flow pumping at 0.5 m vertical intervals-while also noting EC vertical profile values to assure minimal effect on the water column water quality; and (3) a low-flow, purge EC stabilization test with the pump positioned at highest formation water EC values. Sufficient EC values are needed to fulfill Conover's (1980) nonparametric tolerance interval sample size criteria, and to graphically delineate the stabilization plateau. This information will allow you to choose an optimum purge volume that allows a margin for error.

To date there has been little Australian research on repeat victimisation. This is a study of repeat burglary in an area of Brisbane using police calls for service data. We demonstrate: (a) the prevalence of residential repeat victim addresses (‘hot dot’) is of a similar magnitude to that found in studies in the United Kingdom; (b) the time distributions of revictimisation are identical with those found in studies in the UK and elsewhere; (c) ‘hot spots’ (small areas with high crime density) can be identified by statistical analyses of spatial concentrations of incidents; (d) unstable hot spots tend to be temporary aggregations of hot dots, whereas stable hot spots seem to reflect more the social and physical characteristics of certain localities; and (e) the overall incidence of burglary could be reduced by at least 25 per cent if all repeat victimisation could be eliminated. There are a number of areas where concepts and techniques for repeat victim research could potentially be strengthened: (a) clarifying the connections between hot dots and hot spots, particularly through exploration of the concept of a ‘near repeat address’; (b) applying survival analysis to the data on the time periods between victimisations; and (c) using moving average techniques to examine changes in the spatial distributions of burglary over time.

The comparative powers of six discrete goodness-of-fit test statistics for a uniform null distribution against a variety of fully specified alternative distributions are discussed. The results suggest that the test statistics based on the empirical distribution function for ordinal data (Kolmogorov-Smirnov, Cramer-von Mises and Anderson-Darling) are generally more powerful for trend alternative distributions. The test statistics for nominal (Pearson’s Chi-Square and the Nominal Kolmogorov-Smirnov) and circular data (Watson’s test statistic) are shown to be generally more powerful for the investigated triangular (), flat (or platykurtic type), sharp (or leptokurtic type) and bimodal alternative distributions.

The heart rate development and time consumption of four Zimbabwean forest workers engaged in manual harvesting were studied to assess their performance strategy and whether this strategy was affected by differences in fluid consumption. Each worker was studied during eight consecutive working days and produced 2.4 m3 pulpwood/day. They consumed either 0.17 l or 0.6 l of water each half hour with one fluid scheme assigned to each day according to a randomised block (person) design with four replicates (days). All workers were found to harvest large trees at the start of the working day and small trees at the end. All workers took longer to complete their task when on the low fluid scheme, however, the effect on the heart rate development varied for the individual workers as the strategies adopted to accommodate the stress inflicted by the low fluid scheme, varied for the individual workers. It is recommended that sufficient fluid supply during work is accompanied by training of the workers to convey the need and benefits of sufficient fluid consumption

Previous analyses of Australian samples have suggested that populations of the same broad racial group (Caucasian, Asian, Aboriginal) tend to be genetically similar across states. This suggests that a single national Australian database for each such group may be feasible, which would greatly facilitate casework. We have investigated samples drawn from each of these groups in different Australian states, and have quantified the genetic homogeneity across states within each racial group in terms of the "coancestry coefficient" F(ST). In accord with earlier results, we find that F(ST) values, as estimated from these data, are very small for Caucasians and Asians, usually

The adversarial legal system as practised in Australian criminal courts presents considerable difficulties for the statistical expert witness who appears for the prosecution (Crown). In particular, while full disclosure of all evidence is required of prosecution witnesses, the legal “right to silence” of the accused is enforced such that the defense and their witnesses have no similar requirement. The prosecution witnesses may find themselves in court completely unaware of what challenges to their evidence, or self, will be forthcoming. This chapter provides a review of the common situations that can be expected by an expert statistical witness appearing for the prosecution in an Australian criminal case involving the interpretation of DNA evidence. The information has been gained from experiences over a six-year period in the various state and territory legal systems. Eight separate legal jurisdictions are in operation throughout the Australian States and Territories, and some of the difficulties that arise because of differences within the systems are raised and explored. The critical need to communicate effectively to judge and jury is demonstrated through examples of specific difficulties that have been encountered. A number of the strategies that have been found to work successfully in explaining to judge and jury traditionally feared “statistical” issues are presented in full.