Factors Influencing the Filing of Complaints,Their Investigation,and Subsequent Legal Judgment in Cases of Sexual Assault

In Geneva, examination of victims of sexual assault is performed by a gynecologist and a medical examiner. 48% of the victims file a complaint and we wanted to investigate the factors leading to file a complaint, those leading the Prosecutor to go to trial, and those influencing a conviction. Between 2006 and 2012, 676 victims of sexual assault were investigated (averaged age 26 year, mean 22). Information on injuries, perpetrators, and circumstances of the assault was collected and analyzed. The attacker being the ex‐spouse or a friend and the presence of semen were factors leading to file a complaint. The assailant being a family member or ex‐spouse and the presence of genital/anal lesions were factors influencing the Prosecutor. The presence of nongenital lesions, the assailant being known by the victim, influenced conviction. This study shows that the medical examiner plays a vital role in the investigation of cases of sexual assault.     

Y-STR DNA amplification as biological evidence in sexually assaulted female victims with no cytological detection of spermatozoa

Identification of spermatozoa is the biological evidence most often sought in specimens from rape victims. Absence of spermatozoa usually terminates biological investigations, and the victim's testimony can be contested. We assessed the utility and reliability of PCR amplification using Y-chromosomal STR polymorphisms in specimens from female victims of sexual assault with negative cytology.One hundred and four swabs without spermatozoa detected by cytology were collected from 79 alleged sexually assaulted female victims and amplification of Y-STR and of amelogenin was performed.Overall, Y-chromosome was detected and evidenced sexual penetration in 28.8% of swabs. In the population of victims examined more than 48 h after the sexual assault, Y-STR were still evidenced in 30% of the cases. These results show that swabs should be taken from victims for Y-chromosome DNA typing even after long delays between sexual assault and medical examination.     

Legal aspects of sexual violence—Does forensic evidence make a difference?

A survey was done of 307 alleged victims of sexual violence reported to the police departments in Greater Aarhus, Denmark, in 1999–2004. The legal disposition was ascertained and related to victim and assault characteristics together with the forensic medical and laboratory findings. The police pressed charges in more than half of the cases and 11% turned out to be false allegations. Nineteen percent of all cases ended with sentencing of the defendant. Sperm was detected in 35% of the examined and analysed cases, and in 46% consumption of alcohol prior to the assault was reported. Information in the forensic report regarding injury documentation, intoxication, and detection of sperm and DNA match between victim and alleged assailant did not aid in the prosecution of the case. Severe coercion used by the assailant increased the likelihood of conviction. Intoxication estimation and sperm detection suffered from low sensitivity compared with laboratory analyses. Results suggest the need for new research and optimising the sexual assault examination protocol to strengthen the legal impact of forensic evidence.     

Legal aspects of sexual violence--does forensic evidence make a difference?

A survey was done of 307 alleged victims of sexual violence reported to the police departments in Greater Aarhus, Denmark, in 1999-2004. The legal disposition was ascertained and related to victim and assault characteristics together with the forensic medical and laboratory findings. The police pressed charges in more than half of the cases and 11% turned out to be false allegations. Nineteen percent of all cases ended with sentencing of the defendant. Sperm was detected in 35% of the examined and analysed cases, and in 46% consumption of alcohol prior to the assault was reported. Information in the forensic report regarding injury documentation, intoxication, and detection of sperm and DNA match between victim and alleged assailant did not aid in the prosecution of the case. Severe coercion used by the assailant increased the likelihood of conviction. Intoxication estimation and sperm detection suffered from low sensitivity compared with laboratory analyses. Results suggest the need for new research and optimising the sexual assault examination protocol to strengthen the legal impact of forensic evidence.     

Stranger and acquaintance sexual assault of adult males

This study examined victim and assault characteristics and the nature and extent of coercion, violence, and physical injuries among adult male victims of sexual assaults. Client records of three groups presenting to a sexual assault care center were included: males assaulted by a stranger (n = 64), males assaulted by an acquaintance (n = 81), and females assaulted by an acquaintance (n = 106). Study results revealed that male victims of sexual assault tended to be young, single men who reported high rates of vulnerabilities such as homelessness and physical, psychiatric, and cognitive disabilities. Male stranger assailant victims were more likely to experience assaults involving weapons and physical violence. Injuries sustained by victims and services delivered at the sexual assault care center were similar for both male and female clients. The results of this study reveal new information about violence in male sexual assaults and the vulnerability of the male victims.     

Mental health in violent crime victims: Does sexual orientation matter?

The present study investigates victim sexual orientation in a sample of 641 violent crime victims seeking emergency medical treatment at a public-sector hospital. Victim sexual orientation was examined as it: (a) varies by type of violent crime and demographic characteristics, (b) directly relates to psychological symptoms, and (c) moderates the relationship between victim and crime characteristics (i.e., victim gender, victim trauma history, and type of crime) and psychological symptoms (i.e., symptoms of acute stress, depression, panic, and general anxiety). Results showed that lesbian, gay, bisexual, and transgender (LGBT) victims were more likely to be victims of sexual assault. Heterosexual victims were more likely to be victims of general assault and shootings. LGBT victims demonstrated significantly higher levels of acute stress and general anxiety. Moreover, victim sexual orientation moderated the association of type of crime with experience of panic symptoms. Also, victim sexual orientation moderated the relation of victim trauma history and general anxiety symptoms. Results are discussed in relation to victimization prevalence rates, sexual prejudice theory, and assessment and treatment of violent crime victims.     

Sexual assaults in Geneva between 2006 and 2010

In Geneva, all sexual assault victims are examined both by a gynaecologist and a forensic pathologist with special training in clinical forensic medicine. Between 2006 and 2010, 473 victims were examined following such an assault. Over the years, the number of sexual assaults rose steadily. Most victims were aged between 15 and 30 years. The majority of the assaults occurred at night and on the weekend and often happened at the place where the perpetrator or the victim lived. Usually, the offender acted alone and was known to the victim. Many victims hesitate to present for an examination, which makes it difficult to collect evidence. Penetration was usually vaginal and without the use of a condom. Injuries on the body or genitals were seen in only half of the cases for the first ones and in less than one third for the second ones. Quite often (at least in 42 % of the cases), the victim consumed alcohol before the assault and the use of drugs--especially cannabis--was not uncommon either.     

Biological and DNA evidence in 1000 sexual assault cases

Using a Filemaker-based database (DNA Pro-FILES, Synchrone Infosystème Inc.), we have conducted a large-scale study on 1000 sexual assault (SA) cases where a standardized kit was submitted to our laboratory alone or with other types of exhibits. We looked at the likelihood of obtaining good quality DNA evidence, allegedly from the assailant, according to a number of parameters.The overall proportion of SA cases with DNA evidence is nearly 50%. A little more than 30% of SA kits provided DNA evidence while for 16% of cases DNA evidence could be obtained only from other exhibits.The likelihood of obtaining DNA evidence is approximately 50% in teenager and adult SA cases, but much lower for children 10 years old or younger (15%). In children cases, profiles were found mostly on clothing or skin swabs.The likelihood of obtaining DNA evidence from vaginal swabs remains good for up to 3 days after the assault (from 35% on the first day to 23% on the third day). A DNA profile was obtained from approximately 22% of anal/rectal swabs and 41% of skin swabs taken less than 1 day after the assault. Less than 10% of oral washes provided DNA evidence, all having been collected within 24 h of the assault.We found that in bodily samples, a negative result for acid phosphate (AP) is a poor predictor of the likelihood of obtaining good quality DNA evidence. Approximately 15% of vaginal swabs and 8% of anal swabs negative for AP nevertheless provided good quality DNA evidence.     

Evaluation of usefulness of further Y-STR analysis in sexual assault cases on PSA positive samples resulting in female autosomal STR profiling

Samples from male to female sexual assault cases that are positive for the presumptive prostate specific antigen (PSA) test often do not result in a male autosomal STR profile. Due to highly unequal proportions of female and male DNA in typical sexual assault samples, routine autosomal STR analysis often fails to detect the DNA of the assailant, even after differential extraction of the samples. Previous studies have already shown the value of Y-STR analysis in such cases [1]. In Belgium, forensic DNA laboratories are only allowed to perform Y-STR profiling on sexual assault samples by a specific requisition, after routine autosomal STR analysis has been performed. However, a request for additional Y-STR analysis is rather exceptional.In this study, we evaluated the usefulness of further Y-STR analysis. For 100 PSA positive rinses and swabs from male to female sexual assault cases resulting in female autosomal STR profiling, 7% resulted in a full or partial Y-STR profile useful for comparison, using the 23-loci Y-STR PowerPlex Y23 System (Promega). The success rate raised to 12.5% with a higher DNA input in the PCR mix. In conclusion, these results support the usefulness of performing Y-STRs analysis on the sperm DNA extracts to identify the alleged assailant in sexual assault cases.     

The epidemiology of female rape victims who seek immediate medical care: temporal trends in the incidence of sexual assault and acquaintance rape

Women who seek medical care following sexual assault are usually evaluated and treated in an emergency department (ED). Therefore, EDs can be an important source of sexual assault surveillance data. The authors compared the incidence of sexual assault presenting for emergency care in a single county during July to November of 1974 and 1991. Participants included all female sexual assault victims aged 14 and older who presented for ED evaluation. Treating physicians prospectively collected data using standardized forms. The z statistic was used to compare sexual assault incidence. There was a 60% increase in the incidence of sexual assault victims presenting for emergency care in 1991 compared to 1974, primarily due to an increase in the incidence of women presenting to the ED after rapes by known assailants. In contrast, the annual incidence of reported stranger assaults was similar in the two study years.     

The effect of sexual stratification by race on arrest in sexual battery cases

LaFree finds that in most respects officials react more seriously to black assailants who assault white victims than other suspects. Yet paradoxically black assailants who assault white victims are not more likely to be arrested. He explains this apparent inconsistency by proposing that place of incarceration or length of sentence have to do with the seriousness of the offense, whereas arrest has to do with whether the assailant is guilty or innocent. This paper rejects that distinction, arguing that both involve judgments that reflect the influence of similar factors. Several such factors are examined in an analysis of 347 offense reports on sexual battery in Tallahassee over a recent five-year period. The data show that exceptionally cleared cases are the rule in black assailant-black victim (BB) rapes where victims and assailants are mostly acquainted, whereas cases pending predominate in black assailant-white victim (BW) rapes where victims and assailants are mostly strangers. When victims and assailants are acquainted, proportionately more arrests are made in BW rapes than in BB rapes. These findings are consistant with conflict theory’s position that powerful groups enforce sexual-property rules by the differential application of criminal law and punitive sanctions.     

Circumstances surrounding male sexual assault and rape: findings from the National Violence Against Women Survey

Much work in the area of male sexual assault and rape relies on small clinical samples. From these samples, researchers reported that most male victims were physically injured during the attack and that penetration occurred. This work rests on a subsample of 219 men from the 1994-1996 Violence and Threats of Violence Against Women and Men in the United States Survey. Findings from the National Violence Against Women Survey (NVAW) show that the vast majority of male sexual assault victims reported that they were not physically injured during the assault, that a weapon was not used, that there was no substance use at the time of the assault, and that penetration did not occur. Only 29% of male respondents in the NVAW sought medical or psychological help after the assault. Prior work may have overrepresented men who reported being physically injured and/or penetrated. An analysis is presented of how those who presented for help in the NVAW differ from the whole sample. Results show that men who presented for help were more likely to have reported being physically injured during the assault and that penetration occurred. Thus, findings from prior work make sense; however, they may not be representative of male assault victims as a whole.     

Clinical forensic examination findings in assault cases among adolescents

Child and youth criminality has risen markedly over the past 25 years and causes increasing concern to the general public. The clinical forensic examination cases of youth violence victims examined at the Institute of Legal Medicine of the Hanover Medical School and its Oldenburg Branch between 1999 and 2008 were retrospectively analyzed. In all, 55 adolescents (37 females, 18 males; median age 15.5 years) were examined. In most cases the suspect was a close (40.0%) or passing (23.6%) acquaintance. 16 assaults were committed by two or more adolescents jointly. Most of the juveniles were victims of sexual assaults (56.4%). In 15 victims of sexual offences (51.7%) diagnostic findings were obtained on the basis of anogenital injuries and/or the presence of sperm. In summary, the analysis shows that adolescents frequently become victims of sexual assault. In addition, youth violence is often committed in a group.     

How many DNA analyses are performed on adult sexual assault victims in Milan (Italy): A ten-year review

The aim of this study is to evaluate the actual use of serological/DNA analyses in the investigations carried out on adult sexual violence victims in Italy during the years 2006–2015.The victims were assisted in the largest Italian rape center, in Milan (Soccorso Violenza Sessuale e Domestica – SVSeD - Service for Sexual and Domestic Violence).The total number of sexual violence victims examined during the years 2006–2015 (adults and minors) was 3521, in 1697 of cases, biological evidence had been collected, while the number of adult victims (>18 y.o.) examined was 2300, in 1211 of cases biological evidence had been collected.Biological evidence was collected from the victims’ bodies using two swabs in five anogenital areas (labia maiora, labia minora, perineum, perianal and anal/rectum regions) and two swabs in all other skin areas suggested by the victims as areas of possible contact (double swab technique). Clothes were also collected on a case by case basis for the search of biological stains. Despite the proper collection, handling and chain of custody for all the swabs/items collected, serological/DNA analyses were requested in 86 cases out of 1211 only (710%). This percentage dropped to 190% when considering adolescent victims (13–19 y.o.).The reason why Italian Magistrates make little use of the powerful tool of DNA analyses in sexual assault cases, still remains unclear. Legal and procedural aspects are therefore also discussed.     

Screening analysis for medicinal drugs and drugs of abuse in whole blood using ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOF-MS)-Toxicological findings in cases of alleged sexual assault

An ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOF-MS) method for simultaneous screening of 46 medicinal drugs and drugs of abuse in whole blood was developed and validated. The method includes most of the commonly used and abused drugs such as amphetamines, cocaine, benzodiazepines, and opioids. Chromatographic separation of the targeted drugs was achieved using a Waters ACQUITY UPLC coupled to a Waters Micromass LCT Premier XE time-of-flight mass spectrometer. The total chromatographic run time was 13.5min injection to injection. The estimated method LOQ is in the range of 0.06-27ng/g, which is below the therapeutic levels for each of the drugs analyzed but LSD. The extraction recovery ranged from 6% to 197% with median value 95% and mean value 82%. Matrix effect ranged from 81% suppression to 29% enhancement of the signals compared to signals obtained in the absence of biological matrix. The method was tested on 55 authentic forensic toxicology samples confirming the same positive results as found using the routine analytical procedures as well as some additional compounds. Recently there has been considerable attention paid to drug-facilitated sexual assault and the toxicological findings in these cases. As part of a pilot study to investigate the prevalence of medicinal drugs, drugs of abuse, and alcohol in victims of alleged sexual assault, biological specimens were obtained from 167 victims being examined at the Sexual Assault Center in Aarhus, Denmark. The obtained blood samples were analyzed using the novel screening method supported by additional analyses for e.g. THC and alcohol. 124 victims reported they have been drinking alcohol prior to the assault (74%). Alcohol analyses revealed 59 positive findings (48%). 35 of the cases were found positive for one or more drugs excluding alcohol (21%). 20 of the victims reported they have been subject to a drug-facilitated sexual assault (12%). For the victims suspecting drug-facilitated sexual assault, the toxicological analyses revealed four positive for alcohol and nine victims were positive for one or more drugs, with six of the victims found positive for benzodiazepines or other drugs with sedative effects. It was notable that victims tested positive for medicinal drugs and drugs of abuse as well as victims of alleged drug-facilitated sexual assault in average underwent medical examination later than the whole study population.     

The genuine victim and prosecutors’ charging decisions in sexual assault cases

This study examined the effect of victim characteristics and evidence factors on prosecutors’ decisions to file charges in sexual assault cases. Social scientists and legal scholars argue that sexual assault case processing decisions are affected by stereotypes of real rapes and genuine victims. They assert that complainants whose backgrounds and behavior conform to the image of a genuine victim will be taken more seriously, and their allegations treated more seriously, than complainants whose backgrounds and behavior are at odds with this image. We used a sample of arrests for sexual assault made by the Detroit Police Department in 1989 to test these assertions. We combined six victim characteristics to create a genuine victim scale, and we examined the effect of this scale, as well as a number of evidence factors, on prosecutors’ charging decisions. We performed separate analyses on cases with child victims and cases with adolescent or adult victims. We found that the genuine victim scale did not influence charging decisions in cases with child victims, but was theonly significant predictor in cases involving adolescent or adult victims. In contrast, none of the four evidence factors affected charging in cases with adult victims, and only one of these factors was related to charging in cases involving children. These findings suggest that prosecutors attempt to avoid uncertainty by screening out sexual assault cases unlikely to result in a conviction because of questions about the victim’s character, the victim’s behavior, and the victim’s credibility. This paper is based on work supported by the National Science Foundation under Grant No. SES-9010826. Points of view are those of the authors and do not necessarily represent the position of the National Science Foundataion.     

Genitoanal injury in adult female victims of sexual assault

OBJECTIVES: To evaluate the presence and extFent of genitoanal injury among sexually assaulted women and to estimate the risk of injury in subgroups according to the type of assault and to the sexually assaulted women's susceptibility to injury. STUDY DESIGN: A case-control study of 249 women exposed to sexual assault. Injury identified by gross visualization. Women with and without injury were compared. Logistic regressions analyses were performed to calculate the risk of injury. RESULTS: Thirty-two percent sustained genitoanal injury. Anal penetration and assaults on women without prior sexual experience were associated with genitoanal injury. CONCLUSIONS: Most women do not have visible genitoanal injuries. The risk of sustaining genitoanal injury during a sexual assault is higher among women without prior sexual intercourse experience and among women exposed to anal penetration. The severity of the assault is a poor predictor of genitoanal injury.     

Results of forensic medicine victim/perpetrator studies following sex offenses

39.1% of all clinical examinations performed at the institute for legal medicine in Hannover during a period of 9 years were carried out after sexual assault (229 out of 585 cases between 1979-1987). In 74.4% of all women extragenital injuries and in 26.2% of the cases genital lesions could be observed. Vaginal swabs showed sperm at a rate of 44%; spermatozoa could be observed at a maximum delay between assault and examination of 36 hours. Three male victims of sexual assaults and 37 male defendants were examined. On male victim presented superficial lesions of the anus. In 27 penis swabs there could be found spermatozoa (4x), vaginal epithelia (2x) and red blood cells (1x; after intercourse during menstruation).     

Locard's Principle of Exchange,Dental Examination and Fragments of Skin

The transfer of materials between victim and perpetrator was first reported by Locard in the nineteenth century. While in recent years DNA testing has been very successful in matching biological material from crime scenes to perpetrators, the following cases demonstrate that other more time‐honored methods remain useful. Two cases of lethal assault are reported where the victims had bitten their assailants resulting in fragments of the perpetrators’ skin being wedged between their teeth which were discovered during post mortem oral examinations. As the fragments were able to be matched to injuries in the perpetrators, identification was established prior to confirmatory DNA testing. In case 1 a criminal conviction for manslaughter resulted, and in case 2 the identity of the assailant was confirmed. Examination of a properly exposed and illuminated oral cavity may provide useful evidence in assault cases. These cases represent an unusual dental variant of Locard's principle.