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IntroductionThe etiology of adult sexual offending refers to the origins or causes of sexually abusive behavior, including the pathways that are associated with the behavior’s development, onset and maintenance. Even though questions about the causes of sexual offending have been asked for many years, they remain important today, primarily because definitive answers have been exceptionally hard to find. While research has generated important insights about the etiology of sexual offending, our understanding of the causes and origins of sexually abusive behavior arguably remains rudimentary.1 There are multiple reasons why it is important to be concerned with the etiology of sexual offending. First, the development of effective prevention strategies is contingent on having credible knowledge about the underlying causes of sexual offending and victimization. Without credible etiological knowledge, prevention efforts are likely to be haphazard and inefficient. Second, knowledge about causes can help sex offender management professionals manage and mitigate risk more effectively. (For more, see Chapter 6, "Sex Offender Risk Assessment," and see Chapter 8. "Sex Offender Management Strategies," both in the Adult section.) Simply put, knowledge about causes and pathways to offending can provide important insights into the characteristics of various sex offending behaviors (including preferred victim type) and the likelihood that they will persist over time. Third, knowledge about causes can help sex offender management professionals develop more effective treatment interventions. (See Chapter 7 "The Effectiveness of Treatment for Adult Sex Offenders" in the Adult section for more.) Rather than focusing on symptoms or using a one-size-fits-all approach, rehabilitation efforts can target the specific underlying causes and pathways to offending that apply to the individual offender. Fourth, etiological information can inform both discourse and decision-making at the policy level, whether the focus is on sentencing, oversight in the community, civil commitment or any other criminal justice or societal response to sexual offending. In short, knowledge about origins, causes and pathways to sexual offending can play a critical role in the development and delivery of effective public safety strategies. Single-Factor Theories of Sexual Offending BehaviorBiological TheoriesBiological theories of sexual offending have centered on abnormalities in the structure of the brain, hormone levels, genetic and chromosomal makeup and deficits in intellectual functioning. Key research findings concerning the validity of various biological theories follow:
Evolutionary TheoriesEvolutionary theories have been proposed to explain a variety of human behaviors, including sexual aggression. Evolutionary theory views human behavior as the result of millions of years of adaptive changes designed to meet ongoing challenges within the environment. Several theories rely on evolutionary postulates about sexual selection and sexual strategies to explain sexual aggression. One is that sexual coercion is a conditional sexual strategy. In this theory, sexual coercion is postulated to be merely a type of reproductive strategy, as it is in nonhuman species (Bailey, 1988; Malamuth & Heilmann, 1998; Thornhill & Palmer, 2000). Another evolutionary theory views rape as an outcome of a competitive disadvantage for some men that causes them to lack the resources or ability to obtain a mate by more appropriate means (Figueredo et al., 2000; Lalumiere et al., 1996; Malamuth & Heilmann, 1998; Quinsey & Lalumiere, 1995). Another theory describes rape as a "courtship disorder" that results from an interruption in normal mating processes (Freund, 1990; Freund, Scher & Hucker, 1983, 1984).
Personality TheoriesPersonality theories are among the earliest sources of explanation for sexual offending behavior. They emerged based on the work of Sigmund Freud, who believed that sexual deviance is an expression of the unresolved problems experienced during the early stages of an individual’s development. Due to a lack of empirical evidence, Freud’s personality theories have fallen out of favor with etiological researchers in deference to other theories. Later personality theorists, however, suggested that early childhood relationships involving trauma or mistreatment could lead a child to internalize negative attitudes and beliefs about both the self and relationships with others, thus altering how the child perceives sex and his or her role in sexual relationships (Leguizamo, 2002). One of these later personality theories — attachment theory — was first introduced by Bowlby (1988) to explain the relationship between a child and his or her primary caretaker, and how this early relationship affects later adjustment. According to attachment theory, humans have a propensity to establish strong emotional bonds with others, and when individuals have some loss or emotional distress, they act out as a result of their loneliness and isolation. Later research indicates there is a relationship between poor quality attachments and sexual offending. Marshall (1989) found that men who sexually abuse children often have not developed the social skills and self-confidence necessary to form effective intimate relations with peers. This failure creates frustration that causes them to seek intimacy with young partners (Marshall, 1989; Marshall and Marshall, 2000). Seidman and colleagues (1994) conducted two studies aimed at examining intimacy problems and the experience of loneliness among sex offenders. According to these studies, sex offenders have deficiencies in social skills that seriously restrict the possibility of maintaining intimacy. Ward and colleagues (1995) proposed that sex offenders are likely to have difficulty forming attachments with others and will engage in distorted thinking, such as "courting" a child and treating him or her as his lover. Knox (2014) recently found that juveniles who have committed a sexual offense had lower levels of attachment to fathers or father figures than juveniles who have committed a non-sexual offense. Personality theorists also use formulations of personality development based on the results of testing instruments designed to profile personality types. Studies concerning this approach, however, have produced diverse and contradictory findings, and they have been criticized for failing to adequately demonstrate how the results obtained from testing instruments can add to the understanding of the origins of sexually deviant behavior (Stinson, Sales & Becker, 2008). Further evidence is needed to show how certain personality traits relate specifically to the cause of sexual offending behavior.
Cognitive TheoriesCognitive theories address the way in which offenders' thoughts affect their behavior. It is well documented that when individuals commit deviant sexual acts, they often try to diminish their feelings of guilt and shame by making excuses or justifications for their behavior and rationalizing their actions (Scott & Lyman, 1968; Scully, 1990; Sykes & Matza, 1957). These excuses, justifications and rationalizations are commonly referred to as "cognitive distortions" or "thinking errors." They allow offenders to absolve themselves of responsibility, shame or guilt for their actions. Thinking errors on the part of sex offenders have been identified and supported frequently in research. These errors include denial, minimization of harm done, claiming the right or entitlement to the behavior and blaming the victim (Marshall, Anderson & Fernandez, 1999; Ward & Keenan, 1999). The literature also suggests that many sex offenders hold feelings of resentment and use these feelings as justification for their behaviors. Marshall, Anderson and Champaigne (1997) theorized that sex offenders are more likely to be self-protective and self-serving due to low self-esteem, poor relationships with others and emotional discomfort or anxiety. When challenged about their behavior, sex offenders reframe the situation to maintain feelings of self-worth. Another type of cognitive distortion common among sexual offenders is a sense of entitlement, which involves the belief that the need to offend is more important than the negative consequences experienced by the victim (Hanson, Gizzarelli & Scott, 1994). Hanson, Gizzarelli and Scott (1994) found that this sense of entitlement in incest offenders led to decreased self-control, while Ward, Hudson and Keenan (1998) found that thinking errors lead sex offenders to pay attention to information consistent with their distorted beliefs and to reject information that is inconsistent with their beliefs. For example, a child molester may interpret a child's hug as sexual interest because that interpretation conforms to his or her distorted beliefs, or a child molester may ignore a child's crying because it conflicts with his or her beliefs. Further, egocentricity or self-interest allows the sex offender to justify deviant sexual behavior on the basis that it satisfies his or her needs. The offender will see victims as deserving of victimization or may have distorted views of what the victim wants from the offender. He or she may display a consistent tendency to blame others or negate personal responsibility through such statements as "I just couldn't help myself" (Hanson, 1999; Hanson, Gizzarelli & Scott, 1994: Segal & Stermac, 1990; Ward, 2000; Ward, Hudson & Keenan, 1998). Finally, the way sex offenders process both internal and external cues may explain how and why they manipulate information. Research suggests that sex offenders misinterpret social cues and have difficulty recognizing and interpreting the emotional state of others. Further, they do not make good choices based on the information they perceive and do not consider the perceptions of others in making decisions about their own behavior (Keenan & Ward, 2000; Ward, 2000).
Behavioral TheoriesBehavioral theories explain sexually abusive behaviors as a learned condition. Behavioral theories are based on the assumption that sexually deviant arousal plays a pivotal role in the commission of sex crimes and that people who engage in sex with, or have sexual feelings toward, inappropriate stimuli are more like likely to commit sexual violence than those with appropriate sexual desires (Becker, 1998; Hunter & Becker, 1994; Lalumiere & Quinsey, 1994). In behavioral theory, the occurrence of continued deviant sexual behavior (as with all behavior) depends on reinforcement and punishment. Sexual gratification and the perceived lack of negative consequences for sexual offending, coupled with a lack of support for not engaging in sexual offending behavior, increases the likelihood for sex offenses to continue. The key factor is that if the negative consequences of the behavior (punishment) are sufficiently strong, the negative behavior (sex offending) is less likely to occur (Laws & Marshall, 1990). Self-regulation is also a behavioral theory that has been applied to sexually deviant behaviors. Self-regulation involves the selection of a goal and strategies to reach that goal. The goals of sexual satisfaction, intimacy, mood control or other rewards related to sexual deviance can affect recall, judgment and information processing (Ward, 2000). According to self-regulation theory, the goal of engaging in sexually deviant behavior and the strategies employed to reach that goal become automatically integrated into the behavior of the offender because they have been consistently reinforced in the past (Ward & Hudson, 1998).
Social Learning TheoriesTwo primary social learning hypotheses have been suggested as possible explanations for sexual offending behaviors. The first is that children who are sexually abused grow into sexually abusive adults, and the second is that sexually explicit material contributes to sexual offending behavior. Much research has examined the impact of victimization on future victimizing behavior. However, early childhood victimization does not automatically lead to sexually aggressive behavior. While sex offenders have higher rates of sexual abuse in their histories than would be expected in the general population, the majority of perpetrators were not abused as children (Berliner & Elliot, 2002; Putnam, 2003). There is relatively good evidence to support this, including the disproportionate number of women who were victimized as children who do not go on to sexually abuse others (Berliner & Elliot, 2002; Putnam, 2003).
Even so, a large percentage of sex offenders do report being sexually abused as children (Becker, 1998; Craissati, McClurg & Browne, 2002; Graham, 1996; Jonson-Reid & Way, 2001; Seghorn, Prentky & Boucher, 1987; Veneziano, Veneziano & LeGrand, 2000; Worling, 1995; Zgourides, Monto & Harris, 1997). Certain types of offenders, such as those who sexually offend against young boys, have higher rates of child sexual abuse in their histories (Becker & Murphy, 1998; Burgess, Hartman & McCormack, 1987; Burton, Miller & Schill, 2002; Freeman-Longo, 1986; Freund & Kuban, 1994; Garland & Dougher, 1990; Ryan, 2002). For those victims who later become perpetrators, the majority are male (Berliner & Elliot, 2002; Stinson, Sales & Becker, 2008). Therefore, in this regard, researchers have focused on male victims, the way they perceive their abuse and how it affects them later in life. The aspects of the abusive experience that influenced their learning have been of most interest. Using social learning theory, researchers have identified the process through which this learning occurs and the key variables that help to determine whether deviant sexual behavior patterns will be adopted. For example, a child who has internalized the victimization experience as normal or pleasurable in some way is more likely to adopt a belief system that is favorable to offending (Briggs & Hawkins, 1996; Burton, Miller & Schill, 2002; Eisenman, 2000; Freeman-Longo, 1986; Hummel et al., 2000). Several different types of thought patterns may lead more easily to the development of sexually abusive behaviors in victims. For example, the victim may think, "This must be normal" or "It isn't a bad thing because someone who loves me is doing it to me" or even "This feels good and I like it" (Briggs & Hawkins, 1996; Burton, Miller & Schill, 2002; Eisenman, 2000; Freeman-Longo, 1986; Hummel et al., 2000). A child who internalizes these thought processes in reaction to his or her own abuse is more likely to grow into an adult who views sexually abusive acts as less harmful and more pleasurable to the victim. Studies have identified other factors that can play an important role in the link between being sexually abused and later exhibiting sexually abusive behaviors. These include the age of victimization, the relationship between the perpetrator and the victim, the type of sex act and amount of force used, the sex of the perpetrator, the duration of the abuse and the number of perpetrators (Burton, Miller & Schill, 2002; Garland & Dougher, 1990). The younger the victim, the more violent and intrusive the sexual acts, the longer the duration of abuse and the greater the number of perpetrators, the more likely it is that sexually deviant behavior will develop in victims (Burton, 2000; Burton, Miller & Schill, 2002; Hummel et al., 2000; Seghorn, Prentky & Boucher, 1987). The manner in which others respond to an individual who discloses victimization is also a factor that has been shown to be related to the social learning process involved in victimization. An indifferent response or a response of disbelief to a disclosure of sexual abuse has been shown to contribute to a victim internalizing negative sexual behaviors and developing future abusive sexual behavior (Burton, Miller & Schill, 2002; Garland & Dougher, 1990). All of this suggests that the experience of sexual abuse in childhood has some impact on the development of sexually abusive behavior patterns, but exactly how the abuse is modeled and manifested is still somewhat unclear. More research is needed in this area. Research also has examined resilience in victims of child sexual abuse and the protective factors associated with adaptive functioning in childhood, adolescence and adulthood following childhood victimization. This research was recently summarized in a systematic review conducted by Domhardt, Münzer, Fegert and Goldbeck (2015). A total of 37 studies meeting design quality, sample size and resilience definition criteria were included in the review, with resilience being conceptualized as adaptive functioning and/or the absence of psychological disorders. Protective factors were classified within three broad categories: internal factors related to the victim, external factors related to the family of the victim and external factors related to the wider social environment of the victim. Further, the researchers analyzed resilience and protective factors for three different developmental phases based on age: children (aged 10 years or younger), adolescents (aged 11–17), and adults 18 years or older). Across the 10 studies in the analysis that reported resilience rates by age, resilience rates ranged from 10 percent to 53 percent in children and adolescent study samples, and from 15 percent to 47 percent in adult study samples. While Domhardt et al. (2015, p. 487) reported that the wide variation in resilience rates found across studies was in part due to methodological and conceptual differences found across studies, they also suggested that their findings indicate "a range of individual and environmental factors moderate or mediate the well-established adverse impact of childhood sexual abuse across different developmental periods." Protective factors related to resilience included education, interpersonal and emotional competence, control beliefs, active coping, optimism, social attachment, external attribution of blame and social support from the family and wider social environment. Further, the magnitude of the benefit of social support from various sources appears to be a function of the abuse victim's developmental period, with children primarily depending on support from a non-offending parent or caregiver, adolescents depending on support from peers and adults depending on support from a spouse. The researchers called for future research, particularly longitudinal studies, aimed at better understanding how resilience develops over time and how protective factors may interact to promote resilience and buffer the effects of childhood victimization. Another social learning theory related to sexual offending behavior suggests that pornography serves as a model for sexually aggressive behavior for some individuals, encouraging them to engage in behaviors depicted in pornography that they viewed. The literature defines sexually violent pornography as pornography in which women are portrayed in humiliating or degrading situations or are the victims of forced or coerced sexual interactions (Marshall, 1988).2 Based on this theory, an individual who views sexually violent pornography can experience a change in attitudes toward women and can internalize myths about rape. Burt (1980) defined rape myths as prejudicial, stereotyped or false beliefs about rape, rape victims and rapists. Lonsway and Fitzgerald (1994, p. 134) expanded on the concept of rape myths and defined them as "attitudes and beliefs that are generally false but are widely and persistently held, and that serve to deny and justify male sexual aggression against women." Evidence suggests that repeated exposure to sexually aggressive pornography contributes to increased hostility toward women, acceptance of rape myths, decreased empathy and compassion for victims and an increased acceptance of physical violence toward women (Check & Guloien, 1989; Knudsen, 1988; Lahey, 1991; Linz, Donnerstein, & Penrod, 1988; Malamuth & Check, 1980, 1981, 1985). From a social learning perspective, the likelihood that these views will lead to abusive behavior depends on the reinforcement in the learning process. One such reinforcer is a core feature of much pornography: the portrayal of women as desiring and enjoying both the sexual activity and degradation involved in the images (Check & Guloien, 1989; Knudsen, 1988; Norris, 1991; Sinclair, Lee, & Johnson, 1995). Another reinforcer lies in social cues from others — both the participants in the pornography and other viewers. If the participants in the pornographic material seem to be enjoying it and watching it appears to be socially acceptable based on the reaction of others, the viewer is more apt to see the sexually aggressive content as positive and desirable to imitate (Norris, 1991; Sinclair, Lee & Johnson, 1995). Another type of pornography believed to play a role in the etiology of socially learned sexual aggression is child pornography — material that uses either children or technology that makes the participants appear to be children. Social learning theory suggests that individuals use child pornography, internalize this behavior as acceptable and adopt it into their own behavior. Since child pornography is illegal, research on the role of child pornography is somewhat limited. Nonetheless, it is known that child molesters report increased use of pornography prior to sexually abusing children (Howitt, 1995; Marshall, 1988). More recent research has suggested the use of child pornography as a reliable indicator of sexual interest in children (Seto, Cantor & Blanchard, 2006). Across multiple studies, offenders have reported the use of pornography to desensitize and arouse them so they can engage in abusive behaviors with children (Knudsen, 1988; Marshall, 1988). Child pornography also appears to reduce empathy toward child victims (Knudsen, 1988). Portrayals of enjoyment on the part of the children and lack of negative consequences may serve as reinforcers of these behaviors.
Feminist TheoriesAlthough there are many forms of feminist theory, one of the more prominent focuses on the structure of gender relations and the imbalance of power between men and women. This feminist analysis assumes that the elimination of sexual violence is linked to gender equality because it is male power that enables the acceptance and perpetuation of sexual assault. Some feminists have argued that male sex offenders are no different from “normal” men but rather are conditioned within a culture that accepts, tolerates, condones, and even perpetuates sexual violence toward women and children. Perpetrators within this framework are extended to male partners and acquaintances who cajole, pressure, harass, threaten, coerce and/or force women into any sexual behavior to which they do not or are unable to consent. This makes it possible to examine acts of sexual coercion that remain hidden or taken for granted as “normal” social practices within the confines of heterosexual dominance (Chung, 2005; Cossins, 2000). According to Cossins (2000), child sexual abuse is the way some men alleviate a sense of powerlessness and establish their ideal image of masculinity. Because masculinity is learned, according to [some] feminist theorists, in order for a man to experience power, he must engage in accepted social practices (such as sexual violence) that prove his masculinity. Connell (2000) suggests that there can be different concepts of masculinity with varying degrees of social acceptance and power. Connell proposes this as the foundation for why sexual violence occurs. This perspective has given rise to treatment approaches that shift the focus to positively reconstructing a man’s sense of masculinity to exclude the use of sexual violence (White, 2000). Jenkins (1990) also developed an approach to therapy that focuses on what restrains men from engaging in respectful relationships with women, as opposed to what causes them to engage in these relationships.
Multifactor Theories of Sexual Offending BehaviorBelieving that single-factor theories are inadequate, a number of scholars have developed theories that combine multiple factors to explain sexual offending behavior. The most prominent of these theories are discussed below. Finklehor’s Precondition TheoryThe first integrated theory of sexual offending behavior was put forth by Finkelhor in 1984. Finklehor’s theory, which applies only to child sexual abuse, outlines four preconditions that must exist for a sex offense to occur:
Marshall and Barbaree's Integrated TheoryIn this theory, the prominent causal factors for sexual offending are developmental experiences, biological processes, cultural norms and the psychological vulnerability that can result from a combination of these factors. Marshall and Barbaree (1990) proposed that early negative experiences in childhood (e.g., sexual abuse, physical abuse, neglect) cause a child to view his or her caregivers as emotionally absent, and to see him- or herself as being unworthy to receive love or be protected. This results in low self-esteem, poor interpersonal skills and weak coping skills. The presence of antisocial and misogynist attitudes in the home can be aggravating factors. If adolescent males feel inadequate, the theory argues, they are more likely to accept messages that elevate men to positions of power and dominance. Another key feature of the theory is that sex meets a number of psychological needs beyond sexual gratification. These may include an increased sense of competence, elevated self-esteem, personal connection and fulfillment and a sense of achieving the ideal image of masculinity. Marshall and Barbaree suggested that a key developmental task for adolescent boys is to learn to distinguish between sexual impulses and aggression. They argued that this task is difficult because both types of impulses are generated by the same brain structure. Hence, adolescent boys may find it difficult to know when they are angry, sexually aroused or both, and they must learn how to inhibit aggression in sexual situations. Combined with the influx of hormones that occur in adolescence, these factors render the young male vulnerable to developing sex-offending behaviors. Situational factors such as loneliness, social rejection or a loss of a relationship may then trigger the sexually abusive acts committed by adolescents. The more vulnerable a person is to committing a sexual offense, the less intense these situational experiences need to be to trigger sexually aggressive behavior. A later addition to the theory by Marshall and Barbaree is that mood states initially associated with sexual arousal may later be able to elicit sexual desire on their own through the process of conditioning. For example, if a young man frequently uses masturbation to cope with loneliness, eventually the state of loneliness itself creates sexual arousal.
Hall and Hirschman's Quadripartite ModelHall and Hirschman (1991) grouped sex offender personality traits and characteristics derived from other studies into four factors they believed to be most significant in the etiology of sex offending: 1) sexual arousal, 2) thought processes, 3) emotional control and 4) personality problems or disorders. Hall and Hirschman proposed that while all four factors are important, one is generally prominent in the individual sexual offender.
For example, Hall and Hirschman determined that it is not only sexual arousal that is driving the deviant sexual behavior, but the individual’s thoughts regarding the arousal. Thought processes — particularly those involving justifications and myths — may disinhibit an individual to such an extent that deviant sexual behavior seems acceptable or even appropriate. Believing rape myths is a prime example. Negative emotional moods also often precede sexual offending, with anger being an important aspect of negative emotion for rapists and depression being the same for child molesters. These emotional states become so uncomfortable that the individual has further difficulty controlling behavior. The final factor includes negative childhood conditions that contribute to personality characteristics highly associated with personality disorders. They include traits such as selfishness, a manipulative and exploitative personality, lack of remorse and an unstable or antisocial lifestyle. These traits interact with deviant sexual arousal, lack of emotional control or negative thought processes and intensify their respective impacts.
Ward and Siegart's Pathways ModelWard and Siegert’s Pathways Model attempts to combine the best of all of the integrated theories previously mentioned. The model suggests that a number of different pathways lead an individual to engage in sexually abusive behavior. Within each pathway, a unique set of factors contribute to sexual abuse. The theory focuses primarily on the sexual abuse of children by adults. Based on different symptom clusters, Ward and Siegert created five causal pathways for the development of problematic and abusive sexual behavior:
In the pathways model, situational stressors serve as triggers to sexually abuse children. The specific triggers will vary according to the particular profile of causes underlying each individual’s pathway. For example, for offenders who have distorted thought processes, the sexual need combined with the judgment that it is safe to abuse will result in a sexual offense. For an offender with deficits in emotional competence, intensely stressful situations can precede an offense (Ward, Polachek & Beech, 2006).
Malamuth's Confluence ModelThe main idea behind Malamuth’s Confluence Model is that two factors — promiscuous-impersonal sex and hostile masculinity — merge to result in sexually aggressive behavior. A desire for intimacy through sex and the development of long-term relationships or monogamous sexual activity is lacking. The relevance of sexual promiscuity to sexually aggressive behavior is related to evolutionary theory. In short, natural selection has created fundamentally different psychological mechanisms in the brains of women and men with regard to sex and intimacy, resulting in the male’s preference for short-term over long-term mating patterns. If men are adapted for sexual performance in impersonal contexts, then a disinterested or unwilling partner may fail to inhibit or may even entice sexual aggression. Hostile masculinity involves dominating and controlling personality traits, particularly in regard to women. According to Malamuth’s theory, it is in women’s reproductive interest to withhold sex from insufficiently invested partners. Drawing on an earlier study that found that withholding sex angers men (Buss, 1998), Malamuth theorized that if a woman repeatedly withholds sex from a man, or does so at a developmentally significant time, the male may develop a chronically hostile interpersonal style. Thus, the male will be easily angered and resort to coercion and force to assert his dominance whenever he perceives that a woman is threatening his reproductive success (Malamuth, 1996). Dean and Malamuth (1997) introduced a third component to the confluence model — the influence of a high-dominance, low-nurturance approach to interpersonal relationships. This personality style is distinguished by self-interested motives and goals, a lack of compassion or insensitivity and little concern for potential harm to others (Malamuth, 1998). Malamuth suggested that the level of dominance or nurturance traits develops as a result of early childhood socialization and the incorporation of familial and cultural messages. Malamuth also believed the development of a dominant personality style was due in part to evolutionary processes (Dean & Malamuth, 1997; Malamuth, 1998).
Stinson, Sales, and Becker's Multimodal Self-Regulation TheoryMultimodal Self-Regulation Theory was recently introduced as an etiological explanation of sexual offending by Stinson, Sales and Becker (2008). The theory integrates various psychological perspectives and implicates self-regulatory deficits as a key variable in the development of sexually inappropriate interests and behaviors. As part of the theory, Stinson, Sales and Becker (2008) argue that significant self-regulatory deficits resulting from negative childhood experiences combine for the development of deviant sexual interest and arousal. When certain biological and temperamental vulnerabilities are also present, the individual is unable to manage his or her behavior and sexual offending can result. Key to this theory is the premise that sexual arousal becomes linked with a deviant or inappropriate stimulus at some early point in sexual development. This occurs through the mind’s attempt to label the experience of sexual arousal and to associate a source with the arousal. Since this scenario is unlikely to occur on its own, other dynamics are necessary for the connection to occur. The individual would have to normalize the experience in some way and also lack other sources to achieve the same results. Nelligan (2013), for example, found that deviant sexual arousal was correlated with trauma levels in juveniles who commit sexual offenses, and that deviant arousal mediated the relationship between the juvenile’s trauma history and severity of sexual offending. Stinson, Sales and Becker (2008) suggested that behavioral conditioning in the development of abusive sexual behaviors also occurs, as sexual gratification coupled with a lack of corrective action helps solidify the behavior. Over time, the reinforcing effects of these practices, combined with a lack of negative consequences, will contribute to the development of a deviant sexual interest. Stinson, Sales and Becker (2008) also suggested that cognitive beliefs and personality traits could serve as mediators in the development of deviant sexual behaviors. These include egocentricity, a need for excitement and sensation, resentment and a sense of entitlement, impulsivity and irresponsibility. Finally, external factors (e.g., parental support for violence against women) and the development of offense-supportive cognitive beliefs (e.g., a man’s right to control a woman) solidify the behavior in the individual.
SummaryThe field of sex offender management has yet to find a clear explanation or cause for sexual offending behavior. Despite many unanswered questions, research has produced a number of important findings about the etiology of sexual offending:
It also should be noted that other etiological variables that are not addressed in this chapter have been linked to sexual offending. These include alcohol and drugs, domestic violence and mental illness.These variables have been found to be factors in sex offending in some cases; however, there is no scientific evidence that any of these factors are the cause of sexual violence. In addition, there is evidence that some individuals who are already prone to sexual offending behavior become more likely to engage in that behavior when certain situational factors or variables are present. These factors may include limited intellectual functioning, the use of alcohol or drugs, stress within the family/home or loss of a relationship or job. These situational factors, however, do not cause the sexual offending behavior but may increase the likelihood that it will occur in an individual who is already prone to the problem. Although numerous theories concerning the etiology of sexual offending have been proposed and empirically tested, knowledge about the causes of sexual offending remains somewhat rudimentary. This is due, at least in part, to two sets of factors: one related to etiological research and the other to etiological theories themselves. Two major, overwhelming shortcomings are noted from this review of the literature: the problem of sampling used in the research and a lack of intersection and balance among the different theoretical perspectives. Much of the etiological research undertaken to date is based on populations of sex offenders who are either in treatment, in prison or both. This is problematic because the evidence is clear that many sex offenders are never identified by authorities; hence, these studies generally represent a very small percentage of individuals who engage in sexually aggressive or abusive behavior. Many etiological studies also rely on data self-reported by sexual offenders. Because sex offenders are commonly known to engage in cognitive distortions, the validity of their self-reporting remains questionable. There may also be incentives for cooperation in treatment, such as reduced sentencing. Offenders who deny their offenses altogether typically are not included in research. Because many perpetrators who engage in sexually aggressive and abusive behaviors deny it, this implies that a large percentage of the population is ignored in research. Equally important is the propensity of etiological theories to focus on explanations for sexual offending that reside within the individual. Most etiological theories are steeped in the traditional scientific fields of biology, psychology and psychiatry. Hence, the focus largely has been on psychopathological and cognitive-behavioral causes of sex offending. These perspectives, in turn, have strongly influenced policy debates regarding sex offender management and intervention. Few of the integrated theories that have been proposed consider the ways in which social structures and cultural phenomena contribute to sexual offending behavior. Some theories acknowledge situational and environmental factors as related variables or mediators, but the overwhelming emphasis is related to problems within the individual. Consideration of a broader range of theoretical perspectives may be necessary to understand and effectively combat sexual offending behavior. Ending sexual violence may require knowledge and change at the individual, social and institutional levels. Several other dynamics identified in etiological research warrant further study, including the following:
Because much of the etiological research undertaken to date is retrospective in nature, there is a clear need for prospective, longitudinal research, particularly to explore antecedents to sex offending and changes in sexually aggressive behavior over time. Efforts to employ samples that are more representative of the range of individuals who commit sex crimes also are needed, along with studies that include samples of nonoffenders and studies that incorporate the experiences of victims. Victims — both female and male — could contribute valuable information about offender motivations and behaviors through detailed disclosures of their interactions with offenders. This would also allow more opportunity to include the experiences of female victims, as opposed to the current focus on male victims who become sexual abusers. Rather than focusing on why some male victims go on to abuse others, perhaps it is time to ask why most victims, particularly females, do not go on to engage in offending behavior. Including family members associated with the offender could be useful as well. More research into the area of gender relations within the culture is also merited. There also is a need for further study regarding the integration of theories and the ways that different factors involved in sexual offending relate to one another. This need was identified by the national experts at the SOMAPI forum. Success in this area, however, requires more openness and collaboration among researchers with different theoretical perspectives and less loyalty to a particular focus or field of study.
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