Crime Analysis Report

Aggression and Violent Behavior 18 (2013) 520–526

Contents lists available at ScienceDirect

Aggression and Violent Behavior

Explanations of mixed-sex partnered homicide: A review of sociological and psychological theory

Elizabeth A. Gurian ⁎ Norwich University, 158 Harmon Dr., Northfield, VT 05663, United States

⁎ Tel.: +1 8024852844. E-mail address: egurian@norwich.edu.

1359-1789/$ – see front matter © 2013 Elsevier Ltd. All ri http://dx.doi.org/10.1016/j.avb.2013.07.007

a b s t r a c t

a r t i c l e i n f o

Article history: Received 9 November 2012 Received in revised form 16 December 2012 Accepted 7 July 2013 Available online 19 July 2013

Keywords: Partnered offending Homicide Psychological theory Sociological theory

Offending bymixed-sex partnered offenders (i.e., at least oneman and onewoman), no less than offending solely by men, requires explanation. This article begins with an overview of homicide committed by mixed-sex partnered offenders, followed by a brief discussion of sociological theories and then focuses primarily on psycho- logical theories (including transient criminality and stimulation-seeking behavior, hybristophilia and opponent process, folie à deux, obedience and authority) in order to address gaps in our understanding of mixed-sex partnered homicide offending. These theories may help us better comprehend the dynamics between mixed- sex partnered homicide offenders at a sociological and psychological level.

© 2013 Elsevier Ltd. All rights reserved.

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 520 2. Definitions of serial murder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521 3. Understanding partnered serial homicide offenders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521 4. Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 522 5. Psychological theories as explanation for committing homicide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523

5.1. Transient criminality and stimulation-seeking behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523 5.2. Hybristophilia and opponent process theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523 5.3. Folie à deux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524 5.4. Obedience and authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524

6. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525

Criminological theories have emerged out of the need to explain the acts of dangerousmen.Womenwere either not the subjects of these studies, or their actions and participations in crime were dismissed. Work on serialmurder has fallen under this samepedagogy. Initially, acts of extreme violence were identified solely as the responsibility of men.

[Scott (2005, p.163)]

ghts reserved.

1. Introduction

Homicide and serial murder are rare occurrences that typically account for less than 2% of all crimes in many countries, including both England and Wales and the United States of America (Chaplin, Flatley, & Smith, 2011; Federal Bureau of Investigation, 2011). Despite the low number of killings by serial murderers each year (for example, the death toll linked to serial murderers is approximately 1% of all homi- cides in the U.S.A., or approximately two hundred victims per year), they remain an area of intense study (Fox & Levin, 2006) particularly with respect to male serial killers. The recent United Nations Office of Drugs and Crime report on homicide reveals that ‘[c]rime, especially vi- olent crime, is typically a male activity and homicide is no exception…

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men also make up 82% of all victims of homicide, suggesting that the most typical homicide pattern is a case of men killing men’ (Me et al., 2011, p.63, italics added for emphasis). With men comprising the ma- jority of offenders and victims with respect to homicide, it is under- standable that much research has been devoted to understanding homicide through an androcentric lens. Comparatively, the number of partnered (and solo female) perpetrated homicides is lower than solo male perpetrated homicides and less research has been devoted to the subject (for exceptions, see for example Atchison & Heide, 2011; Farrell, Keppel, & Titterington, 2011; Gurian, 2011; Jones, 2008). Two possible reasons for this occurrence are that crimes by violent partnered offenders are under-reported or underestimated. Information on these offenders is scant, of uneven quality, and shown to be from widely dis- parate sources. Therefore, this current research may serve to further stimulate interest in the subject, thus filling gaps in our knowledge.

A number of theories have been sought to explain acts of criminal ho- micide and serial murder. However, these theories tend to occur after the fact (Riedel & Welsh, 2008), and either omit to include partnered offenders and women or do so only marginally (Batchelor, Burman, & Brown, 2001; Belknap & Holsinger, 2006). A number of psychological theories identified by Scott (2005) and others also attempt to explain se- rial homicide offending. For example, the MacDonald triad links cruelty to animals, bedwetting and fire setting with violent and homicidal be- havior (MacDonald, 1963). Researchers have found these characteristics primarily in samples of solo male offenders (Felthous & Kellert, 1987; Merz-Perez, Heide, & Silverman, 2001). Research findings on samples of primarily male homicide offenders creates questions regarding the applicability to other types of homicide offenders (i.e., partnered and solo female offenders) and this is particularly so in relation to psychop- athy and violent behavior (Elliott, 1992; Fox & Levin, 2006).

This article begins with an overview of homicide committed by two or more ‘partners’ followed by a review of psychological theories in order to address gaps in our understanding of partnered homicide offending. By convention, theories can be categorized as cultural, socio- logical, biological, or psychological, with a focus on male offenders. Leonard (1982), for example, contends that criminological theories were constructed by and about men, which explain male behavior in- stead of human behavior. These theories may have less applicability to- wards understanding the criminality of women, particularly when they are involved in crimes of homicide with one or more male partners. Therefore, theories less commonly cited in the literature are also included, which particularly relate to women, in order to present a more balanced portrait of human homicidal behavior. It is also impor- tant to note that while some of the behaviors discussed in this article could be classified as mental disorders (folie a deux, paraphilia), by convention, they are categorized under psychological theory.

2. Definitions of serial murder

Unlike single acts of criminal homicide, which are thought to date as far back as the period of Neanderthals,1 the term ‘serial killer’ has argu- ably only come into practice within the past 30 years (Hazelwood & Douglas, 1980); however, the crime of serial murder is not a new one. Locusta the Poisoner2 (a woman) is cited as potentially the first documented serial murderer (Leon, 1998), while Jack the Ripper3 is commonly cited as the first case of serial murder to be reported by the contemporary press. Although serial killing is a rare phenomenon,

1 The earliest known murder case is thought to have occurred over 50,000 years ago and involved a Neanderthal man who was stabbed in the chest with a human weapon by a right-handed assailant (Trinkaus & Zimmerman, 1982).

2 Locustamurdered the Emperor Claudius during the first century A.D., in Gaul, another rival to the throne, and a number of other victims as a ‘poisoner-for-hire’ (Leon, 1998).

3 Jack the Ripper murdered at least five women in theWhitechapel area of London. He achieved notoriety through the letters he sent to the police and local press detailing the murders and because the case remains unsolved.

cultural, historical, societal, and religious influences continue to contrib- ute to current stereotypes and myths about serial murderers. The lack of ability to accurately predict who, where, when, and often why these individuals will strike, and the methods they employ, generates an atmosphere of fear and fascination surrounding this subject.

Serial murder differs from other forms of homicide based on several key characteristics, including a minimum timeframe (with ‘cooling off’ period between homicides), body count (at least two or more by the same offender(s)), and general pattern to the killing (e.g., victim selec- tion, method, and motive). In comparison, mass murder occurs when a number of victims are killed at one instance and lacks the ‘cooling off’ period characteristic of serialmurder. Serialmurdermay less commonly be referred to as ‘multiple murder’.

Commonly used definitions of serial murder may also exclude cer- tain groups of offenders or victims; ‘For those in law enforcement, serial killing generally means the sexual attack and murder of young women, men, and children by amalewho follows a pattern, physical or psycho- logical’ (Hickey, 2010, p.26, italics added for emphasis). Many offenders and victims are excluded by definitions such as this; Seagrave (1992, pp.4–5) claims, ‘[t]here are no female counterparts to a Bundy4 or a Gacy5, to whom sex or sexual violence is part of the murder pattern’; this statement discounts serial murderers such as Karla Homolka, who reportedly participated in the rape and torture of young girls with her husband and partner, Paul Bernardo.6

3. Understanding partnered serial homicide offenders

Unlike solo homicide offending, homicide by partnered homicide of- fendersmay be both a participation and spectator event. Elements, such as power and gratification, also serve to distinguish the relationships within these partnered homicide groups. For example, power and grat- ification can be experienced ‘not only through the deaths of victims but also through getting others to do their bidding’ (Hickey, 2006, p.199). Partners in crime may operate symbiotically, contributing to each other's wish for power. Fox and Levin (2006) contend that a sharing of tasks neutralizes feelings of personal responsibility, while risks with personal safety that oncemay have been unthinkable become an option when engaged in partnered activity with a like-minded individual. This argument is similar to Darley and Latané's (1968) ‘bystander effect’. In- dividualsmay accept promises given the right set of circumstances. That is, abnormal situations make normal people do ‘crazy things’, especially if they perceive a self-serving purpose in doing so (e.g., profit, power, and protection) (Fox & Levin, 2006; Sutherland, 1947). Some male and female offenders may never have committed their crimes had they not been exposed to group dynamics and the power of persuasion and ma- nipulation (Akers, 1985; Hickey, 1991). Leaders may experience a sense of power and gratification through influencing others to commit crimes, while followers also enjoy being involved, but becomemurderers under another's enticement (Hickey, 1991). The dynamics within partnered offending groups are varied, and it is likely that any or all of these con- tentions feature throughout the course of these criminal relationships.

When women commit crimes with a male accomplice, the accom- plice is typically a boyfriend or husband (Gurian, 2011). For example, a male gatekeeper to the criminal world may be in a position to provide criminal contacts and opportunities to their female partner. Cooper (2000) contends that the male (dominant partner) generally initiates the crime (that is, the woman is passive and emotionally dependent).

4 Ted Bundy confessed to murdering 30 young women across the U.S. 5 John Wayne Gacy (the “killer clown”) murdered 33 young men and boys and buried

many in a crawl space underneath his home. 6 Homolka's partner, Paul Bernardo, began showing interest in her younger sister,

Tammy (age 15), during their relationship. On Christmas 1990, the two performed sexual acts on an unconscious Tammy (drugged with animal tranquilizers provided by Karla, who worked in a veterinarian's office), who choked on her own vomit and died during the course of the evening. After Tammy, Karla and Paul kidnapped, raped, tortured and killed two young girls in separate incidents.

7 While databases include homicide counts, it would be difficult to accurately match statistics for a given year to offender names due to (previously noted) differences in defi- nition or reporting. For example, depending on the source, homicide may be counted by offender, victim, or incident, which complicates identification of multiple offenders.

8 For example, Hickey (2010) lists 14 cases of Japanese partnered and solo female serial killers in his research; however, many of their primary details could not be readily verified due to language differences. Despite the lack of accurate victim counts, the Ishikawa case was included in the sample of partnered serial homicide offenders becausemost of the pri- mary details, including convictions and sentences, could be ascertained.

522 E.A. Gurian / Aggression and Violent Behavior 18 (2013) 520–526

It is thought that women may participate out of fear of being left or are threatened into compliance (Cooper, 2000). As the female offender rationalizes feelings of guilt and shame from being involved in the crime(s), shemay either ‘become sanguine in [her] role’ or derive sexual and/or emotional gratification (Cooper, 2000, p.270). Female offenders are commonly noted as having the following potential characteristics, which defense teams may use as excuses for criminal behavior: insecu- rity, low self-esteem, social isolation, poor education, and having been abused as children (Cooper, 2000). However, an alternative perspective on women's engagement in partnered criminal homicide concerns romantic attraction; in other words, there may be a mutual willing- ness to trust and emotional and/or economic dependence (Weerman, 2003), meaning that these partnerships are potentially based on interdependency.

What some killers could never become alone, they may aspire to collectively as inhibitions and fears become dissipated by the interac- tion of the partnership (Hickey, 1991). Fox, Levin, and Quinet (2008) claim that approximately 25% of all serial killers operate in teams, while Thompson and Ricard (2009) contend that approximately one- third of female serial killers act with a partner(s). However, while partnered serial offenders, like other serial offenders, have been docu- mented for many years, little attention has been given to the nature of partnered offending (Hickey, 1991; van Mastrigt, 2004).

Warren and Hazelwood (2002, p.76) assert that sexual sadists use ‘a variety of verbal, physical, and sexual behaviors involving the domi- nation, control, and suffering of partners […]. These behaviors are designed to establish, in the most violent instances of behavior, the sense of having ultimate control over the life, and death, of another’. Hazelwood, Warren, and Dietz (1993) suggest that the male sadist uses a process which exploits vulnerabilities in their female partner which turns her into a compliant accomplice. This term has been used to explain the actions and behaviors of a number of women involved in cases of partnered serial murder. Under this paradigm, the men are endowed with extraordinary skills of control, coercion, and influence (Dietz, 1996), while the women are viewed as weak, feeble-minded, and vulnerable. Hickey (1991, p.83) contends that serial murderers ‘rarely seek out those who are as physically or intellectually capable as themselves [to murder]. Instead, by either randomly or carefully targeting victims, serial murderers mentally and/or physically stalk their prey’. Therefore, it would seem that the female accomplice must be too intelligent to serve as a proper victim, but weak enough to be manipulated.

This ideation of the female offender as a victim coerced into crime (Caspi, Lynam, Moffitt, & Silva, 1993; Mathews, Matthews, & Speltz, 1989) remains controversial and is opposed by some researchers (Baskin & Sommers, 1998;Matravers, 2001). Despite the prevailing pic- ture ofwomen as coerced co-offendersMaher (1997, p.2) states, ‘for the most part, women [co-offenders] are portrayed as the hapless victims of strongermore experienced, and in some cases, “evil”males’, some re- searchers are also beginning to see thesewomen as active participants in their crimes (e.g., Ajzenstadt, 2009;Myers, Gooch, &Meloy, 2005; Scott, 2005). Additionally, Alarid, Marquart, Burton, Cullen, and Cuvelier (1996) report that some women seek out male co-offenders because they are attracted to ‘bad boys’ and the ‘fast life’. Research examining the potential role of females in criminalizing males is lacking (van Mastrigt, 2004). Hakkert (1998, p.463) states that girls ‘have a height- ening effect on the criminal behaviour of boys because boys like to act tough around [them]’. As Warr (2002, p.80) asserts, ‘what is clear is that cross-sex influence [in all its forms] deserves serious attention’. Further co-offending research is needed to identify differences in group dynamics, offender characteristics, and behaviors.

Thus, the explanationswhichhave beenproposed to date, character- ize females in partnered homicide offending as being weak and trivial- ized killers. However, much research is based on samples of males and then generalized to include female homicide offenders, particularly with respect to serial murder and partnered offending behaviors. In

order to further examine these explanations, the following sections crit- ically explore a range of specific psychological theories that attempt to explain partnered serial homicide. In particular, this article examines the relevance of these theories for female homicide offenders who com- mit serial acts of murder with at least one male partner. These theories are included because there is a lack of specific research on partnered homicide offending. This examination allows for building a theoretical framework from which comparisons can be drawn to androcentric re- search. However, before turning to the psychological theories, it is im- portant to first discuss the sampling and data procedures for gathering this sample of partnered serial homicide offenders.

4. Methodology

Every attempt was made to generate a comprehensive sample of partnered serial homicide offenders, including exploring the research literature; the research literature provided the majority of names of fe- male serial murderers (e.g., Hickey, 2010; Scott, 2005; Vronsky, 2007). Criminal Justice Abstracts (2009) (an electronic criminology database from SAGE Publications) was also utilized in order to gather research literature on serial murder. The LexisNexis® (2009) electronic database was used to search for media reports of partnered serial murder cases (that is, current crimes reported after the published research literature included in this study). Lists of serial murderers are also available from popular crime websites on the Internet (e.g., Crime Library, 2008; Crimezzz, 2006); names gathered from these sources were cross-referenced primarily with the research literature and also the media accounts. Another source for partnered serial murderers in the U.S. is from death row lists. Resources such as Federal Bureau of Investi- gation (FBI) and Home Office databases were also consulted. However, these sources do not provide complete lists of names of serial homicide offenders, only homicide statistics.7 Despite the lack of a comprehensive list of partnered serial murderers, a number of these cases are consis- tently identified. However, it is acknowledged that there are likely to be some offenders who were not included in this sample. For example, a major difficulty in gathering this sample of offenders resulted from non-inclusion of some women in partnered serial murder cases. For example, Josefina Rivera is not commonly mentioned alongside Gary Heidnik in the murders committed in Pennsylvania. Therefore, it is suspected that there are at least several more cases of partnered serial murder that would fit the parameters of this study, but due to the diffi- culty in detecting these cases, they remain undiscovered.

The literature relating to serial murderers is typically in the form of case studies (e.g., Bugliosi & Gentry, 1974; Soothill & Wilson, 2005). However, Kraemer, Lord, and Heilbrun (2004) argue that an overview of the population of serial murderers is needed before one can under- stand how case studies relate at an individual level or distinguish ‘com- mon elements from unique aberrations’. The population of partnered serial murder offenders is too small to select a random representative sample; therefore all partnered serial murderers identified through the research literature and other sources are included in this research. Keeping these limitations in mind, names and key criteria (such as method, victim selection, timeframe, and sentence)were cross referenced among the different sources in order to improve the reliability and va- lidity of the data and to reduce the influence of unreliable or question- able data; cases were not included in which primary details could not be ascertained between at least two difference sources.8

Table 1 Offender sample (1900–2006).

Total number of cases Number of offenders (N = 34) (N = 111)

Partnered serial 34 111 M = 63 F = 48

523E.A. Gurian / Aggression and Violent Behavior 18 (2013) 520–526

The sample of offenders includes 34 cases of partnered serial homicide offenders (n = 63 males, n = 48 females; n = 111 total offenders) (see Table 1). Again, for the purposes of this research, the term ‘partnered’ refers to a partnership of at least one male and one female homicide offender (cases of same sex serial murderers working together as partners are rare and were not included due to disparate sample numbers).

The offenders included in this samplewere restricted to the following criteria: the criminal homicide(s) must have occurred between 1900 and 2006 (for accuracy of data as cases prior to this timeframe tend to be reported with exaggerated victim counts); and the offenders must have committed a minimum of two separate acts of criminal homicide with a ‘cooling off’ phase between incidents9 (crimes of mass murder10

are not included). No age limits were applied, nor were any offenders excluded based on ethnicity or international location.

5. Psychological theories as explanation for committing homicide

Despite a need by researchers to pathologize so as to explain the seemingly inexplicable (that is, labeling an offender with a mental dis- order creates a different framework for murderers in that something is wrong with that individual), some of these individuals have led the appearance of ‘normal lives’, complete with families and friends who are inevitably shocked to discover that someone they knew and trusted was living a double life. Prediction of homicidal behavior, therefore, continues to elude researchers, although general trends have been iden- tified ex post. A single cause for committing homicide is unlikely; expla- nations are more likely to be multi-factorial with different influences.

Atchison and Heide (2011), in a recent article on the application of sociological theories to the Manson family, call for researchers to apply psychological theories to homicide offenders. The psychologi- cal theories explored in the following sections discuss a number of concepts which may be used to explain partnered serial homicide offending, including: transient criminality and stimulation-seeking be- havior, hybristophilia and opponent process, folie à deux, obedience, and authority.

5.1. Transient criminality and stimulation-seeking behavior

Transient criminality, developed by Mawson (1987), is a less com- monly cited psychological theory to explain homicide by women and men.11 Mawson (1987, pp.6–7) defines transient criminality as ‘a pattern or characteristic way of offending; the category includes indi- viduals forwhom criminal deviance represents an occasional and usual- ly not very serious aberration from an otherwise law-abiding existence’. While this theory typically applies to ‘occasional’ and ‘not very serious’ crimes, it may have applicability to partnered homicide offenders. One might theorize that the women in the partnered homicide groups, particularly the serial groups (in which they tend to be younger than

9 This may consist of hours, days, weeks, or months. 10 Mass murder may be defined as when ‘… several victims are killed within a few mo- ments or hours’ (Hickey, 2006, p.7). 11 This theory is similar to Matza's (1964) theory on delinquency in drift, in which juve- niles fluxuate between extremes in their behavior (drift). Matza (1964) suggests that ju- veniles ‘drift’ between conservative and criminal behavior through a gradual process that molds the individual's behavior. Once a crime is committed, the juvenile feels guilt and seeks to balance their behavior by acting in a socially accepted manner.

their male partners), experience transient criminality as they make the transition from young adulthood to adulthood.12 The uncommon pairing of these women with an experienced male partner might pro- duce a criminal dynamic that results in murder. This dynamic is poorly understood; however, it is possible that without the critical pairing of the partners, neither would have committed murder. Mawson (1987, p.30) states, ‘[o]ne of the most frequently mentioned factors is some form of separation experience involving attachment figures and/or fa- miliar surroundings. The category of separation includes death, aban- donment (or the threat of abandonment), and forced or voluntary separation from occupational activity, migration, etc.’ It is possible that the criminal dynamic in the partnered homicide groups resulted in an escalation to murder through the woman's fear of abandonment by her partner or to maintain the thrill and excitement in the relationship. An example of this concept is the case of Karla Homolka, who began by raping young girls with her husband before escalating to murder. To transgress societal expectations of her sex with masculine forms of ag- gression requires a kind of permission from her male partner. Morris (1987, p.76) suggests that learning crime includes techniques and also ‘rationalizations, justifications, and attitudes’, a concept echoed prior in Sykes and Matza (1957) techniques of neutralization. Partnered offending might offer an opportunity for young women to commit crimes that are not commonly associatedwith female violence, including sexual assaults and murder which they might not commit in adulthood.

A potential link to the theory of transient criminality is the potential for a predisposition of stimulation-seeking behavior (SSB) (Mawson, 1987). Mawson theorizes, ‘the concept of a strong predisposition for SSB refers to (a) a low threshold for SSB, and (b) a tendency to overreact with a more intense and persistent SSB to a given stimulus than would be shown by other individuals of comparable age, sex, race, or social background’ (1987, p.199). The concept of stimulation seeking ‘empha- sizes the idea of seeking stimulation within and from the familiar inter- personal and physical environment’ (Mawson, 1987, p.200). Mawson (1987, p.200) (emphasis in original) argues that individuals with this predisposition would ‘tend to have a low threshold for approaching fa- miliar persons and a tendency to react with more intense and persistent attachment behavior than others of comparable age, sex, race, or social background’. The attachment behavior between these individuals is suggested to be exceptionally close and to be described as intense, jealous, dependent, or aggressive (Mawson, 1987; Smith & Hanson, 1975). Additionally, ‘[a]ccording to theories of assortative mating, persons with similar characteristics tend to seek each other out. Thus, people with a strong predisposition for SSB would be expected to form couples (Dominion, 1972)’ (Mawson, 1987, p.105). Studies also reveal that individuals who have experienced different forms of abuse show ‘an uncanny ability to become involved with and marry people who tend to accentuate rather than solve their problems’ (Steele & Pollock, 1974, p.106). Although there is limited research that examines the relationship between/among partnered homicide offenders, this theory may begin to explain the contributing behaviors of those who commit homicide as a mixed-sex team.

5.2. Hybristophilia and opponent process theory

Another, less frequently cited psychological theory that may explain whywomen commit homicide is hybristophilia: a predatory-type para- philia commonly associated with women. Hybristophilia comes from the Greek word hybridzein (that is, ‘to commit an outrage against some- one’) and philo (that is, ‘having a strong affinity or preference for’) (Vitello, 2006, p.198). Therefore, sexual arousal is dependent upon a partner known to have committed an outrage or crime (for example, rape, murder, or armed robbery) (Money, 1989). Hybristophiles may be victims of physical or sexual abuse, which can result in low self-

12 Much research has been developed on the importance of age as a risk factor for offending (see Newburn, 2007; Sampson & Laub, 2003).

14 In Los Angeles, California, between the months of June and August 1980, Carol Bundy and Douglas Clark kidnapped, raped, and killed six known victims. Bundy died in prison while Clark is serving his sentence on death row. 15 Under the direction of Charles Manson, the ‘Manson Family’ (a group of six primary

524 E.A. Gurian / Aggression and Violent Behavior 18 (2013) 520–526

esteem and insecurity, thus making them ‘vulnerable to deviant sexual preferences and criminality’ (Vitello, 2006, p.198). However, othersmay wish to collaboratewith a violent offender in order to express their own violent tendencies. This relationship can also be beneficial to the male offender. Charles Starkweather13 is noted as saying, “[Caril Ann was] something worth killing for… she put the spark and thrill into the killing” (Erlbaum, 1999). Money (1999) argues that hybristophiles partake in ‘opponent process learning’ (that is, operant conditioning in reverse). This theory is based on homeostatic mechanisms in the human body bywhich new demands aremetwith a change in the bodi- ly processes (A process). Afterward, the opposing process (B process) gradually returns the body to its resting state. Solomon and Corbit (1974) observed that the A process generally dominates while the B process is slow and inefficient; however, over time the B process may become faster, more efficient, and dominant. Therefore, the opponent process turns negative into positive (for example, bungee jumping is initially viewedwith terror, but after a few trials, fear becomes exhilara- tion and ecstasy) (Money, 1999; Zuckerman, 1979). Baumeister and Vohs (2004, p.97) state ‘[a]ccording to opponent process theory, the ini- tial and natural panic reaction to falling calls forth an opposing reaction that resembles euphoria in order to restore the body to its homeostatic state’. These authors also suggest that:

[t]his model can account for the emergence of sadism even if people are naturally averse to inflicting harm. The first time one hurts or kills someone, one has a strong negative reaction, but as one con- tinues to perform such acts, the opponent process gradually yields more and more pleasure…. Enjoyment of sadistic acts is mainly reported or admitted by people who have been at it for a relatively long time.

[Baumeister and Vohs (2004, p.97)]

This theory may help to explain the dynamic in partnered serial murder cases, in which the female becomes initiated to criminal be- havior through her typically more experienced male partner. The thrill of ‘getting away’ with the first murder negates the initial fear of being apprehended, and the partnered serial murderers will continue mur- dering until the exhilaration fizzles or they are eventually apprehended.

5.3. Folie à deux

The intermingling of two people's fantasies, delusions, or fears is commonly referred to as folie à deux. Clinically, psychiatrists describe it as shared psychotic disorder (SPD), typically referring to cases in which paranoid–delusional persons succeed in instilling their lovers with their own insanity (Silveira & Seeman, 1995). Paranoid–delusional individuals are generally charismatic and the person they are with is usually hyperimaginative and suggestible; thus the paranoid–delusional person's version of reality becomes the dominant one (Silveira & Seeman, 1995). Serial murderer Ian Brady suggests that this process can only occur if the target person is ‘fertile soil in which such proposals can readily take root’, meaning that the criminal desire must already be present (Ramsland, n.d.). Although based on the theorizing of a convicted serial murderer, this claim negates the theory of a ‘compliant victim’, instead implying that a person who becomes involved in crime, regardless of another person's influence, already had criminal tendencies.

There is generally an initial uncomfortable state of confusion and perplexity, which creates a drive to understand the other's madness (Silveira & Seeman, 1995). Ultimately, there can also be an active decline at work and a desire to give in to the more untamed mind, an urge that may be more operative in criminal pairs than in non- criminals who suffer SPD (Silveira & Seeman, 1995). Serial killer Carol

13 Starkweather killed 11 victims, including the family of accomplice Caril Ann Fugate.

Bundy14 has said regarding her relationship with Doug Clark, ‘Part of me was desperately terrified…. Part of me was drawn to the apparent danger in this, the risk that I was facing…. It was sort of a love–hate type of complex. Wanting, yet not wanting. Being afraid, yet being attracted to what I was afraid of’ (Pearson, 1998, p.187). Silveira and Seeman (1995) contend that the most common delusion in folie à deux is persecutory: the belief that someone or something is out to de- stroy the couple. The next most common delusion is the delusion of grandeur: the shared belief that the couple (or team) is better and more entitled than those around them. These delusional persons (for example, theManson girls)15 typically experience self-imposed iso- lation. Substance abuse over time with alcohol, marijuana, or cocaine plays a frequent role in this spiraling process. One partner is gradually exposed to the other's deranged outlook and progressively accommo- dates their madness. This theory may help to explain not only paired serial murderers, but also larger groups as well, particularly when drugs or alcohol are involved. For example, Charles Manson, leader of the Manson Family was noted to use drugs as a form of mind control.

5.4. Obedience and authority

In 1963, Milgram devised a laboratory experiment described to re- search participants as pertaining to punishment and learning.Milgram's experiment was designed to create an extreme moral conflict in the participant: ‘to obey the experimenter but at the cost of continuing to harm a protesting victim, or to sidewith the learner but, in so doing, dis- obey the experimenter and ruin the experiment’ (Miller, 2004, p.195). Milgram (1963) reported an unexpected finding in his initial paper on the experiment: 65% of the participants continued obeying orders to the end of the shock series. Groups including psychiatrists and under- graduate studentswere providedwith a description of the experimental situation and asked to estimate the obedience rate of 100 hypothetical participants; overall, the respondents underestimated the experiment's results by extremely wide margins (Milgram, 1963). The results from Milgram's experiment have been likened to genocide occurring during the Holocaust and in areas such as Rwanda and Bosnia: these ‘scenarios revealed ordinary people willing to treat other people with unimagin- able cruelty […] the coercive influence of authority figures seemed to be of critical importance’ (Miller, 2004, p.196, italics added for emphasis). For example, participants in Milgram's experiment ‘became involved in a graduated escalation of harming, the endpoint of which was very un- likely to be foreseen at the start’ (Miller, 2004, p.197). Milgram (1963, p.377) states, ‘One might suppose that a subject would simply break off or continue as his conscience dictated. Yet, this is very far fromwhat hap- pened’. Therefore, a large number of ‘seemingly good people engaged in extremely destructive actions under an experimenter's [co-offender's] orders’ (Miller, 2004, p.197). Miller's findings have since replicated (e.g., Burger, 2009).

The results from Milgram's experiment might also be compared to the dynamics of partnered homicide, particularly those involved in cult activities.16 Males in partnered serial groups are generally older and have prior criminal experience compared to their female partners, thus (at least in the initial stages of the relationship) likely serving as an authority figure to his younger, criminally naïve counterpart. Staub (1989) contends that while obedience is an important component, it is not the ultimate motive for genocide or mass killing. Instead, Miller (2004, pp.29–30) (italics in original) suggests the motivation to obey typically arises from ‘a desire to follow a leader, to be a good member

and at least a dozen peripheral members) is responsible for the murders of at least seven victims in 1960s California. 16 Cults typically feature a dynamic and charismatic (male) leader who directs and shapes the cult in terms of ideology and action.

525E.A. Gurian / Aggression and Violent Behavior 18 (2013) 520–526

of a group, to show respect for authority. Those whowillingly accept the authority of leaders are likely to have also accepted their views and ide- ology…people join rather than simply obey out of fear or respect’. There- fore, it is important to consider not only how leaders gain authority but also how the motivations of the group evolve as a whole (Miller, 2004).

In a study designed to test the validity of Milgram's obedience para- digm, Sheridan and King (1972) substituted the human learner-victim with a puppy that was actually given graded shocks by the participant. The study was further refined to examine differences in male and female subjects: It would not be unreasonable, in view of nurturance typical of females, to suppose that women would be less willing than men to inflict harm on a cute puppy. Further, common observation suggests that womenmight be better able than men to confront or ma- nipulate authority figures such as the commanding E [experimenter]. Conversely, the submissiveness of the female role might lead to greater compliance (Sheridan & King, 1972).

Interestingly, all of the female subjects in Sheridan and King Jr.'s experiment complied with the experimenter's instructions to shock the puppy through to the end of the voltage scale (these results are statis- tically significant, p b .02) (Sheridan & King, 1972). In contrast, slightly more than half (54%) of themale subjects obeyed to the endof the shock scale. Sheridan and King (1972) explain:

45 Ss [subjects], both male and female, were asked, in a classroom setting, to indicate how much shock they would deliver if they had been Ss in the experiment. Only three Ss (twomale and one female) indicated they would go beyond 300 V. When females were asked to predict how far the “average woman” would go in shocking the puppy, 86% of them predicted that the “average woman” would shock no higher than 150 V, and no one predicted that the “average woman” would go as far as 450 V.

Age is a critical variable in Sheridan and King (1972) experiment; Milgram used more mature subjects unlike Sheridan and King Jr., whose female subjects were all in their teens. These findings have rele- vance to the results from this study as well, in which, as previously noted, the females in the partnered serial groupwere generally younger than their more criminally experienced, older, male partner(s). The importance of obedience and authority to young women beginning a criminal career with an older male partner may help to explain their subsequent actions, particularly in the case of serial murder. However, this theory fails to account for partnerships in which the female(s) in the group exhibit a leadership, rather than follower, mentality (particu- larly the single-incident homicide group, in which the women are generally older than their male partner(s)). This theory also fails to explain the female offender's obedience to the male partner over the larger authority of law or society.

6. Conclusion

There is no shortage of explanations formurder or serial murder, but some are more plausible in attempting to explain partnered homicide than others. Riedel and Welsh (2008, p.94) argue that these explana- tions tend to occur after the fact (‘[p]ostdicting, in contrast to predicting, is a theoretical analogue to Monday morning quarterbacking’, in which criticisms or judgments can be made with the benefit of hindsight) and with an excess of false positives (in which an individual is perceived to have a certain condition, but does not). Riedel and Welsh (2008, p.94) suggest:

When physical theories attempt to explain a rare event, such as a large asteroid hitting the earth, they make use of general laws. But sociological and psychological theories have ill-defined bound- aries, are imprecise, and are largely untested. They provide few in- sights and no predictions when applied to serial killers, who are extremely rare and remarkably diverse.

Early theories of crime either ‘fail to include girls (and women) or if included, theorize about them in sexist and stereotypicalways’ (Belknap & Holsinger, 2006, p.48; see also Batchelor et al., 2001). While re- searchers have written books on homicide offending (see Egger, 1990; Fox & Levin, 2006; Hickey, 2010), most continue to focus predominately onmales. As a result, there is less comprehensive theorizing available on female offenders who commit murder with at least one male partner.

Several of the theories discussed in this article also support the idea that a womanmay be initiated into conducting criminal acts through an experienced male partner. However, unlike the concept of the ‘compli- ant accomplice’ (Hazelwood et al., 1993), this article attempts to explain the dynamics between the woman and her partner(s) without denying her agency in the crimes. For example, these theories generally high- light factors, such as age difference and criminal experience, and may explain the partnered criminal dynamic through such elements as esca- lation tomurder through thewoman's fear of abandonment by her part- ner, stimulation-seeking behavior, ormotivation to obey. These theories begin to provide potential insight into partnered serial homicides, an area which is lacking in research.

Offending bywomen, no less than offending bymen, requires expla- nation. However, no one theory or type of theory discussed in this arti- cle encapsulates an answer as to why women commit murder with a partner. It is possible that an examination of a number of different theories may serve to provide a more gendered set of risk factors and mechanisms which may explain mixed-sex partnered homicide offending. In other words, based on this review, there are several risk factors which may be particularly, but not, perhaps, exclusively, rele- vant to women who commit murder with a male partner (for example, partneringwith criminally experienced peers, thrill-seeking or attention- seeking behavior, abuse, age, insecurity, and rejection). Through this examination, this article attempts to add to our understanding of partnered serial homicide by exploring less commonly cited theories in the literature. These theories may help us to better comprehend the dynamics between partnered homicide offenders; they might also help us to understand some of the offending patterns of partnered offenders in general. Scott (2005, p.166) argues, ‘[t]he ontological assumption is being made that there is little value added in our under- standing of the dominant form of criminal behavior if we include these non-dominant forms. The assumption is also being made that the dominant form of an offender class has been correctly identified and that we have the appropriate understanding of the phenomenon at all’. Yet, the offending behaviors ofwomen reveal a very different profile from that of their male counterparts, and this has various implications for society, media and the criminal justice system.

Acknowledgments

The author would like to thank her doctoral supervisor, Professor Loraine Gelsthorpe, and Drs. Amy Nivette, Amy Woodbury Tease and Gina Sherriff for their thoughtful comments on earlier drafts of this paper.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

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Elizabeth A. Gurian is an Assistant Professor at Norwich University in the School of Justice Studies & Sociology.