Chapter 10: Sex-Related Offenses
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Chapter 10
Sex-Related Offenses
Objectives
1. Discuss interview procedures and investigative questions for sexual assault cases.
2. Discuss victim-centered and trauma-informed sexual assault response.
3. Explain how investigators can be sensitive to the needs of transgender assault victims.
4. List some of the unique elements of interviewing a deaf victim of sexual assault.
5. Identify the signs and symptoms of sexual abuse of elders.
6. Explain why women do not report rape/sexual battery to the police.
Introduction
This chapter discusses how to best interview sexual assault victims, which can be a most delicate
and challenging task for the criminal investigator. The investigator must obtain all the necessary
information yet do so with respect and concern for the victim. It is absolutely imperative that the
investigator does not in any way pass judgment on the victim, which would result in
revictimization. This chapter primarily focuses on sexual assaults that are typically directed
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Lecture Notes
I. The Law
The term sex-related offenses covers a broad category of specific acts against adults, children,
males, and females. Rape or sexual battery is legally defined as the crime of a person having
II. Sex-Related Investigations
As such, when a sexual assault is reported to law enforcement, investigators must treat victims
with respect, compassion, and sensitivity. If a victim of sexual assault is treated well, they are
much more likely to cooperate with the investigation, ensuring justice not only for the victim, but
for the community at large.
Despite the gender or sexual identity of the victim, when police and medical examiners are
III. Victim-Centered and Trauma-Informed Response
There has been a shift over the past few decades to a victim-centered and trauma-informed
response model. Victim-centered response is, simply, a law enforcement investigation that
A. Interview Procedures and Investigative Questions
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Today, best practices for sexual assault investigations make clear that there should be a
preliminary victim interview as part of the initial law enforcement response and a subsequent
B. The Follow-Up Interview
Much like the minimal fact interview, the follow-up interview should be conducted using
C. Type and Sequence of Sexual Acts during an Assault
By analyzing the sequence of acts during the assault, the investigator may determine whether
the offender was acting out a fantasy, experimenting, or committing the sexual acts to punish
or degrade the victim. For example, if anal sex was followed by fellatio (oral sex—mouth to
penis), the motivation to punish and degrade would be strongly suggested.
Almost without exception, police record the theft of items from rape victims. The victim
should be asked to inventory items. Missing items fall into one of three categories:
evidentiary, valuables, and personal.
IV. Transgender Victims of Sexual Assault
The transgender community is subject to much stereotyping, bias, and to high rates of sexual
abuse and assault. Transgender individuals must be dealt with using the same victim-centered
and trauma-informed response as all other victims, which may be challenging for many police
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Police sexual violence (PSV) is an egregious form of sexual misconduct that involves sexual
harassment and violence, including rape and other sexual assault, perpetrated by police officers.
Unfortunately, it has emerged as a critical issue for law enforcement agencies.
V. Deaf Victims of Sexual Assault
Sexual assault victims who are deaf face unique issues not encountered by the hearing. The
A. Reluctance to Reach Out
Many deaf victims may be reluctant to reach out to agencies that serve sexual assault victims
because most of the providers are hearing and do not have systems for effectively
communicating with deaf people.
B. Improving Police Response
Service providers and deaf community members agreed that law enforcement must improve
VI. Elder Sexual Abuse
As an increasing percentage of population grows older, an increase in elder sexual abuse is
observed.
A. Signs and Symptoms of Sexual Abuse
Emotional symptoms of anxiety and depression with accompanying feelings of fear and
B. Assisted-Living Facilities
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Sometimes, access into the facility is not tightly controlled, thereby allowing sexual predators
easy access to the patients.
C. Nursing Homes
Three common nursing home sexual abuse victim profiles include these: (1) physically
disabled older resident; (2) cognitively impaired resident; and (3) physically impaired younger
D. Early Recognition and Detection
Early recognition and detection of abuse and reporting of cases means knowing the physical
E. Interviewing Elder Victims of Sexual Abuse
The following therapeutic tasks are important to develop trust with the elder in order to do an
accurate assessment of the complaint of sexual abuse.
• Tell the senior what to expect.
F. Signs of Physical Trauma
• Signs of physical trauma include observable objective evidence of injury such as
bruises, abrasions, lacerations, and/or bleeding.
VII. Why Women Do Not Report Rape to the Police
Studies have shown that many women are reluctant to report rape to their local police. The
reasons most often given include the following:
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• Lack of belief in the ability of the police to apprehend the suspect
• Worries about unsympathetic treatment from police and discomforting procedures
VIII. False Rape Allegations
False rape allegations are a difficult subject for law enforcement. Ultimately, law enforcement
officers have a responsibility to ensure that no one is falsely accused of sexual assault: the stakes
IX. The Victim and Physical Evidence
A. Instructions to the Victim
The officer responding to a reported sexual assault should make a great effort to ensure that
B. Semen and Hair as Evidence
Semen that contains sperm and hair that has the root attached can now be identified through
DNA typing as coming from a specific individual. Note that the terms semen and sperm are
C. Information for the Examining Physician/Sexual Assault Nurse Examiner
The medical personnel responsible for examining the victim should be provided with all the
available facts before the physical examination. Under no circumstances should a male
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D. Collection of the Victim’s Clothing
The victim’s clothing should be collected as soon as possible. Each article of clothing should
E. The Role of the Investigator in Securing the Rape Scene
It is the criminal investigator’s job to collect, catalog, and store physical evidence for later
F. Incidence of Errors in the Collection of Evidence
As items are collected, the investigator must carefully label the items and store them in such a
way that they are preserved intact and uncompromised for later laboratory analysis. Keeping
G. Collecting Samples for DNA Analysis from Suspects
In 2013, the U.S. Supreme Court ruled that a police officer has the right to take DNA samples
H. Sexual Battery Examination
Most hospitals or crisis centers responsible for the collection of evidence from sex-offense
victims have developed sexual battery examination kits.
X. Condom Trace Evidence
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Manufacturers produce condoms using a variety of materials, both natural and synthetic. In
A. Exchangeable Traces
Condom manufacturers add finely powdered particulates to prevent a rolled-up latex condom
from sticking to itself. Particulates found in different brands include cornstarch, potato starch,
and lycopodium (a powder found in plants), as well as amorphous silica, talc, and other
minerals.
B. The Value of Condom Trace Evidence
Condom trace evidence can assist investigators in several ways. It can help prove corpus
delicti, provide evidence of penetration, produce associative evidence, and link the acts of
serial rapists.
A serial rapist likely will use the same brand of condom to commit repeated acts. Moreover,
repeat offenders whose DNA profiles have been stored in a computer data bank may be likely
to use a condom when committing subsequent crimes.
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C. Guidelines for Evidence Collection
Investigators need not make any drastic changes in their usual procedures in order to include
the possibility of condom trace evidence. The following guidelines will assist criminal
investigators and medical examiners in collecting this valuable evidence.
XI. Record of Injuries
A careful record should be made of the victim’s injuries and be included in the report. The
examining physician can provide details of injuries not readily noticeable.
A. Electronic Evidence
There are a number of electronic resources germane to sexual assault investigators. Sources of
video may include ATM cameras, neighborhood security cameras, nightclubs, retail locations,
XII. Drug- and Alcohol-Facilitated Sexual Assault
A drug- or alcohol-facilitated sexual assault is one that occurs when a person is made vulnerable
or is incapacitated by the ingestion of drugs or alcohol. Sexual offenders’ increasing use of date-
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A. Drugs of Choice
As already indicated, the two drugs that are most commonly used by sex offenders to
facilitate their crimes are Rohypnol and gamma hydroxybutyrate.
B. Males as Rape Victims
People tend to think that only females are the victims of date rape or stranger rape. However,
that is an incorrect assumption.
C. Other Date-Rape Drugs
A host of other depressants and benzodiazepines can debilitate sexual assault victims. Valium,
D. Evidence Collection and Processing
Because victims may be unaware, or may only suspect, that an assault has occurred, law
E. The Investigation
Law enforcement officers cannot rely on forensic toxicology reports alone because the drugs
may already have left the victim’s system by the time evidence collection is initiated.
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F. Evidence
When the investigation reaches the point at which a search warrant can be obtained for a
suspect’s residence, car, or place of work, the following items should be included in the
search warrant:
• Packages of Rohypnol and other drugs
XIII. Sexual Motivations in Homicide Investigation
Male homosexual homicides involving interpersonal violence often present patterns of injuries
that can best be described as overkill. These injuries are usually directed to the throat, chest, and
abdomen of the victims. There may also be certain psychosexual wounds present in homosexual
A. Murders Involving Forced Anal Sex and/or Sodomy
Sodomy is noncoital sex—usually anal or oral sex. Homosexual homicides involving forced
anal and/or oral sex are to some extent analogous to rape-homicide among the heterosexual
population.
B. Extreme Sexual Self-Mutilation
Law enforcement officers should be aware of the degree to which individuals are capable of
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C. Lust, Murders, and Other Acts of Sexual Perversion
Some sexually motivated homicides involve bizarre and sadistic methodologies such as sado-
XIV. Autoerotic Deaths/Sexual Asphyxia
Autoerotic deaths/sexual asphyxia occasionally occur as a result of the masochistic activities of
the deceased. Typically, this form of death involves a white male who is found partially
suspended and sometimes dressed in women’s clothing.
A. The Psychological Autopsy
Occasionally the medical examiner or police investigator is confronted with a death and must
determine if it is the result of autoerotic or suicidal intent. For resolving questions about the