Electronic Journal of Sociology (1998)

ISSN: 1198 3655

Researching Serial Murder:
Methodologial and Definitional Problems

Ronald Hinch
Department of Sociology and Anthropology
University of Guelph
[email protected]

Crysal Hepburn

Direct all correspondence to Ronald Hinch
[email protected]
Phone: 519-824-4120 ex. 2195
fax: 519-837-5961]

Abstract

This paper examines issues related to the definition and study of serial murder. It examines definitional issues such as the notion that serialists are male, the notion that the killings are not for profit, the claim that the killers and the victims are strangers, and the conception of the victims as powerless. It examines methodological issues such as problems with both quantitative and qualitative data, and the creation of serial killer typologies. The paper argues that reliance upon narrow definitions, questionable data gathering, and the creation of typologies based on these definitions and data distort the analysis of serial murder and serial murderers. Suggestions are made for improving the scholarly study of serial murder

The image of Jack the Ripper has captured the popular imagination for more than a century. His exploits have been the focus of innumerable films, television shows, books and newspaper features. Other accounts of serial murder, some fictional, some about real killers, fuel an insatiable public appetite for tales of gruesome murder. In the process the media often creates a distorted image of serial murder and serial murderers. As Jenkins (1994) has argued, the end result is an image of the serial murderer as an uncontrollable monster.

Criminology degrees teach you about the nature and causes of crime.

The media, however, are not alone in fostering this image. Dietz (1996) has suggested that scholarly investigation also plays a role in creating the stereotype. In this paper, we examine how three aspects of scholarly research help perpetuate the stereotype. We examine the definition, the research techniques, and the typologies used in the study of serial murder.

The Definition

Egger's (1990)1 frequently cited (Geberth and Turco 1997; Keeney and Heide 1994; McKenzie 1995) definition of serial murder provides a convenient point to begin our discussion. Egger says a series of killings may be classified as serial murder when:

...one or more individuals (males, in most known cases) commits a second murder and/or subsequent murder; is relationshipless (no prior relationship between victim and attacker); is at a different time and has no connection to the initial murder; and is usually committed in a different geographic location. Further, the motive is not for material gain and is believed to be for the murderer’s desire to have power over his victim. Victims may have symbolic value and are perceived to be prestigeless and in most instances are unable to defend themselves or alert others to their plight, or are perceived as powerless given their situation in time, place or status within their immediate surroundings (such as vagrants, prostitutes, migrant workers, homosexuals, missing children, and single and often elderly women). (1990:4).

While each component of this definition is open to challenge, we focus on just four aspects. We show how (1) the notion that the killers are male, (2) the assumption that they kill mostly strangers, (3) the notion that they don't kill for financial gain, (4) and the notion that their victims are powerless people have contributed to the stereotype.

The Killers Are Male

While some researchers (Egger 1990; Leyton 1986) argue that the small number of female serialists makes systematic analysis of female serialists impractical or even impossible, other analysts have limited their research in this way for theoretical and/or ideological reasons. For example, to show how patriarchal structures contribute to violence against women, some radical feminists explicitly limit their efforts to examining male serialists (Cameron and Fraser 1987; Caputi 1987; 1989; 1990: Chesler 1993).

Other analysts disagree. They point out that there is strong empirical evidence which not only indicates that there are female serialists, but that there is sufficient data upon which to begin theorizing about female serial murderers. For example, Hickey's (1997) data shows that female serialists account for almost 15% of known serialists operating in the United States from 1800 to 1995. These percentages of male and female killers are comparable to the percentages of male and female murderers found among one time killers. Similarly, Keeney and Heide (1994), Cluff, Hunter and Hinch (1997), and Scott (1992) have shown that theorizing about female serialists using the existing data base can tell us much about the overall social, cultural and political context within which serial murder takes place.

Serialists kill in gender specific ways. Males are more likely than females to use brute force. According to Hickey’s (1997) data, males are significantly more likely to shoot, strangle/suffocate, stab, or bludgeon their victims. Only 5% of males use poisons to kill. On the other hand, women are more likely to use poison to kill (35% use poison only, and 45% use poison in combination with some other means of killing). It is also true that males are significantly more likely to kill strangers than are females, and that females are significantly more likely to kill family members than are males (see the next section on the relation between victim and offender). Finally, their motivations for killing differ. According to Hickey (1997:p. 153,218) the most frequent motives for male serialists are ”sex sometimes“ (46%), "control sometimes“ (29%), and ”money sometimes“ (19%). For female serialists, the most frequent motives are ”money sometimes“ (47%), ”money only“ (27%), and ”control sometimes“ (13%). The data, therefore, would seem to imply that gender roles are important in terms of understanding how and why serialists kill.

Excluding female serialists from either the definition of serial murder, or even from study samples, has resulted in an unnecessary and unscholarly limitation of inquiry. Including female serialists allows for the examination of the role played by socio-cultural and socio-structural factors in creating serial murderers. That is, it points the way to extending the explanation for serial murder to areas other the individual pathology.

The Victim and Offender are Strangers

Eggers’s (1991) definition of serial murder suggests that typically there is no relation between the serialist and the victim. There is, of course some basis in fact to substantiate this claim. Male serialists are more likely to kill strangers than they are to kill persons known to them. However according to Hickey (1997), almost one third of a male serialist's victims are persons known to him. Furthermore, a female serialist is as likely to kill persons known to her as she is to kill strangers. This suggests that Egger’s limitation that the typical serial murder victim is a stranger is unwarranted and misleading. While it is true that male serialists kill significantly more strangers than persons known to them, it is clearly unwarranted to exclude from the definition of serial murder the possibility that some victims are persons known to the offender. As Hickey (1997) says, assuming that the victim and the offender are strangers amounts to speculation rather than scholarly analysis.

Not for Material Gain

It has been common practice for analysts to exclude events in which the killer profits financially from the crime. Consequently, many studies have excluded professional contract killers, as well as so called black widows(women who kill husbands sequentially), simply because the motivation for the killings is assumed to be different from the ”true“ serial killer. This exclusion is usually based on the assumption that serialists are extrinsically motivated while ”real“ serialists are intrinsically motivated. For example, Leyton writes:

This multiple murder for profit is merely one form of making a living, one in which the murder is incidental to the goal. Those who practice this "profession" would undoubtedly follow another if they were offered more money. We are concerned with those who appear to kill for its own sake, those for whom killing alone is the apparent goal (1986:24- 25).

However, Gresswell and Hollin (1994) point out some analysts claiming to exclude extrinsically motivated killers have actually included them. Holmes and DeBurger (1988) claimed to exclude killers who kill for profit, but their classification of hedonistic-comfort killers implies an extrinsic reason, i.e., for comfort. Gresswell and Hollin (1994:5) also argue that murders committed to "...prevent a sexual assault victim identifying an assailant, may also be considered extrinsically motivated acts." Thus it would appear that the exclusion of extrinsically motivated killers is not complete. More important, Hickey (1997) notes that almost one quarter of the male serialists, one third of the team serialists (two or more killers working together), and one half of the female serialists in his sample killed for money. Therefore, to assume that serial killers do not kill for financial gain once again amounts to speculation. The evidence clearly demonstrates that some serialists kill for profit. This means that excluding some serialists, such as professional assassins or hit men is unjustified and unjustifiable without more careful study.

It could be argued that the exclusion of extrinsically motivated killers, especially those who kill for profit, amounts to an ideological conception of serial murder. It is ideological because it excludes evidence on the basis of preconceived beliefs that serial killers are intrinsically motivated, while ruling out . priori that serial killing may be the product of socio-cultural and/or socio-structural variables.

The Victims Are Powerless

There is good reason to question the assumption that the victims of serial murder are powerless people. Leyton (1986) argues the modern multiple murderer is attempting to level the social structure. Multiple murderers of previous eras had been members of the higher strata who primarily killed members of the lower strata. By contrast, the modern multiple murderer comes from the lower strata and kills representatives of the higher strata. Leyton explains:

The major homicidal form of the modern era is the man who straddles the border between then upper-working class and the lower-middle class. Occasionally...they continue a metaphor from the earlier era and discipline unruly prostitutes and runaways. Much more commonly, however, they punish those above them in the system -- preying on unambiguously middle-class figures such as university women (1986:297).

It should be noted here that Leyton’s reference to university women as representatives of powerful interests must be considered from the point of view of the serialist. Some male serialists see university women as powerful. These killers may perceive that they are disadvantaged relative to university women because these women are able to do something the killers are unable to do, or are prevented from doing. For example, Leyton suggests that Ted Bundy was motivated to kill young women, many of whom were students, because they represented those forces which were blocking his social mobility. He was avenging his failed university career in law by killing those people he perceived to be in a more powerful position than himself.

In attempting to move the discussion of serial murder toward consideration of structural factors, Leyton agrees with feminist analysts of serial murder (Cameron and Frazer 1987; Caputi 1987; 1989; 1990). Both seek to expand the study of serial murder beyond examination of individual pathology. They argue there is a connection between social structure and serial murder. Leyton looks toward class structures, while feminists examine patriarchy. Expanding the definition in this way allows the analyst to assess the societal contexts which shape and nurture individual pathologies.

Measuring the Menace

No research technique is foolproof. Whether qualitative or quantitative techniques are used, both methods pose particular problems for the researcher of serial killers. This section examines these problems showing how misuse and misapplication of research techniques contributes to the stereotypes associated with serialists.

Problems With Qualitative Data

Any textbook on qualitative research lists potential methodological problems. These problems include difficulties in gaining access to subjects, difficulties with the reliability of the information provided by the subjects, and the possibility of interviewer bias or contamination. We will examine each of these issues as they impact upon the study of serial murder.

Gaining access to research subjects is a problem for all researchers, but is particularly difficult when studying serial murder. Access to subjects may be denied for many different reasons. Access may be restricted by penal institutions, or by the killer's lawyer(s) (O'Reilly-Fleming 1995). Sometimes subjects simply refuse to cooperate. They may not see an advantage for themselves in agreeing to be interviewed. Even when they agree to be interviewed, many may be unwillingly or unable to talk freely about their crimes (Holmes 1989).

Quite apart from problems of gaining access, there are problems with reliability. It is common for researchers to inadvertently bias or contaminate the data. Hickey (1997) argues that some researchers conducting lengthy interviews with serialists may become too close to their subjects. They may unconsciously contribute to the notoriety of the killer, providing him or her with the publicity he or she seeks. Sometimes serial killers engage in gaming, telling the interviewer what they think the interviewer wants to hear (Hickey 1997). Others may revel in the glory and attention by making themselves and their stories fit the image. They may confess to more murders than they committed. Jenkins (1994) argues that both Ted Bundy and Henry Lee Lucas engaged in such behaviour. Clearly, if not properly attuned to the killer's attempts to manipulate the interviewer, the interviewer may pass on the killer's misinformation.

An additional problem with data gathered via interviews is that these interviews are retrospective. result, they demand that the killer be able to accurately recall and reflect upon his past. This causes additional problems and the interviewer must consider the length of time that has passed between the murders and the interview. "Hindsight can easily distort reality and mold it to the psychological needs of the offender (Hickey 1997:231)." Interviewers should expect distorted explanations and thinking from serial killers.

Interviews, of course, are not the only sources of data. For example, Leyton (1986) relied upon newspaper accounts, diaries, case studies, criminal justice system records, and other archival information. None of these sources is completely reliable. Newspaper accounts, for example, sometimes provide extensive details about specific serialists. These details are usually based on trial testimony, but may sometimes be supplemented with other information obtainable through investigative journalism. Journalists, however, are notorious for reporting hearsay. They are often accused of being more interested in getting a story than in disseminating accurate information. The news media are also renowned for an emphasis on sensational crimes to the exclusion of more mundane murders which do not fit the stereotype (Jenkins 1994: Kiger 1990). Thus, newspaper accounts are a major source of misinformation.

Biographies, diaries and case studies, while rich in descriptive data, may also be sources of misinformation. Criminal records, trial transcripts, abstracts and archival information are as reliable as the information they contain and there is little reason to believe these sources contain all the necessary information. Further, a case history may be selected for its sensational appeal. This is clearly what led to the production of at least four mass market books (Burnside and Cairns 1995; Davey 1994; Pron 1995; Williams 1996) claiming to give the true story of the exploits of Paul Bernardo and Karla Homolka. As Ratner (1995) puts it, specific cases draw attention because their exotic nature appeals to the voyeur. The problem here is that these case studies are skewed in favour of stereotypical images or public expectations of the characteristics of serialists. By failing to critically assess the sampling bias which enters into the selection of "suitable" material, stereotypes are perpetuated. A more critical assessment of this material may lead to the conclusion that they do not hold any theoretical interest.

For example, the books published in an attempt to cash in on the notoriety of Paul Bernardo and Karla Homolka offer slightly different versions of the events, and significantly different explanations for why Homolka did what she did (Burnside and Scott 1995; Davey 1994; Pron 1996; Williams 1996). Even though these books base their accounts on court evidence, readers would find it confusing that the evidence presented from one book to the other is sometimes contradictory. As for Homolka’s roles in the murders, the authors clearly disagree on motivation. Davey, Pron and Burnside and Cairns portray Homolka as an abused woman who killed while under the domination of an abusive, violent husband. Williams, as well as Pearson (1997), another commentator on this case, implies that Homolka was far from a submissive and abused woman. These authors argue that she was an active and willing participant in the deaths of the three school girls. The point here is that even books based on similar records, including court records, are not necessarily going to give the reader an accurate interpretation of the data.

Problems With Quantification

Most experts agree that the number of serial murders and of serial murderers is unknown (Egger 1990a; Gresswell and Hollin 1994; Hickey 1997; Holmes 1989; Holmes, Hickey and Holmes 1991; Jenkins 1994; Maxfield 1989; O'Reilly-Fleming 1996). It has been estimated that between 10 and 500 serial killers are active at any time in the United States (Egger 1990a; Kiger 1990; O'Reilly- Fleming 1996). In Canada, estimates range from 5 to 30 (Ratner 1996). The variation in these estimates can be attributed to a variety of problems with data sources: arbitrary definitions; small samples; samples biased toward only known/apprehended serial killers; and samples relying upon secondary sources such as biographies or newspapers. These alternative data sources have been used primarily because official data are not reliable.

For example, the FBI collects data from law enforcement agencies across the United States and publishes it in the Uniform Crime Reports(UCR). The Supplemental Homicide Report(SHR), part of the UCR, provides additional information about victims, offenders and circumstances. The intention is to reflect all criminal offenses that come to the attention of the police.

The data, however, are incomplete and unreliable. First, because reporting is voluntary, the information is incomplete (Kiger 1990; Williams and Flewelling 1987). Second, there may be organizational pressures within particular police jurisdictions not to alarm the public about the possible existence of a serial killer in that area. This may prevent reporting and/or effect homicide classification procedures (Kiger 1990; Williams and Flewelling 1987). Third, homicide data records only those crimes known to the police. Missing persons and undiscovered bodies are excluded.

The importance of this third observation is that many unidentified bodies are found each year and there have been attempts to link the number of unidentified bodies to serial murder. Annual estimates in the United States place the number of unidentified dead between 4,000 and 5,000. Some authors claim that many of these are victims of serial killers. For example, Radford (1992) estimates that most the 3,500 unidentified female victims of murder each year in the United States are victims of serial murder. This is an unwarranted claim which Jenkins has clearly denounced:

The problems with this statistic were, or should have been apparent. If, in fact, 3,500 females fell victim to serial killers each year during the mid- 1980s, this would have accounted for some 70 percent of all murders of women and girls. Apart from being implausible as it stands, this figure would also leave little room for the domestic murders that, according to the femicide literature, are believed to be so endemic a problem (1994:142).

The actual proportion of the unidentified dead who are the victims of serial murder is unknown (Hickey 1997: Egger 1990a; Jenkins 1994: Kiger 1990). In the United States, it is not mandatory for coroners to report the discovery of unidentified bodies to a centralized data bank. Also, coroners need no formal training for the position. Their reports to the FBI may contain unreliable information about the cause and time of death (Kiger 1990). Further, cause of death cannot be determined from badly decomposed bodies, which are then unlikely to be counted as homicides. Sometimes, bodies may be found where cause of death can be classed as homicide, but the victims were killed in previous years. These victims are not likely to be submitted as additions to a revised homicide count for that year (Kiger 1990). Moreover, many victims of a serial killer may not be classed as homicides at all. They may be assumed to have died of natural causes (eg. nursing home and hospital patients).

As a result, homicide rates are underestimated and the consequent analyses are inaccurate (Jenkins 1994; Kiger 1990; Williams and Flewelling 1987). UCR/SHR data reflect only the number of deaths labelled as homicide by the police. They do not necessarily reflect the actual number of deaths in a given year. At this point, numerical estimates of serial killers and victims based on this data are questionable. Thus, it is unwarranted to assume that serial killing is on the rise as has sometimes been claimed. It is also inaccurate to attribute most stranger or unknown homicides to serial murder. This limits our ability to understand the nature and extent of the problem, and or course, inflated estimates provoke fear of a serial killer epidemic.

A further complication arises in the inability to use existing data sources to make cross cultural or cross national comparisons. Although serial murderers are known to exist in most countries, there have been few attempts at cross national comparisons. Cross national analysis is impeded by definitional problems, differential reporting patterns, and data inaccessibility. Thus, more effort must be put into improved reporting standards (a point which will be discussed below) to allow for systematic comparison if we wish to advance understanding.

From all this is should be clear that traditional social science data sources have not been useful in the study of serial murder. Kiger succinctly states the dangers of the dearth of quantitative data:

Although idiographic research provides useful insights into the lives and possible individual-level etiology of serial murderers, it is also important to accurately quantify the problem. Without accurate quantitative assessments of the extent of serial murder, we will be unable to develop informed typologies, theories, and policy decisions. Indeed, we run the risk of creating a social problem, the magnitude of which may be greatly exaggerated (1990:35-36).

Thus, while the literature provides no decisive answer to questions regarding the number of serial killers or the number of victims of serial killers, it purports to do so. In doing so, it often uses only those data which deal with narrowly defined acts of serial murder, i.e., the most sensational cases. As Kiger (1990) says, we must be careful not to allow sensational, unreliable statistics, premised on misleading stereotypes, to obstruct or misinform our analysis. Given these problems, researchers must be held accountable for the numbers they present. As Jenkins (1994) argues, moral panics about serial murder are frequently the product of ideological campaigns for law and order. For example, Jenkins argues that the moral panic over serial murder that arose during the 1970s in the United States

...coincided exactly with a strong political trend toward a reevaluation of the etiology of social problems, a general tendency toward viewing wrong-doing and deviance as issues of personal sin and evil rather than social or economic dysfunction (1994:9).

Finally, since academics contribute to police investigations, data must be accessible. O'Reilly-Fleming (1996) argues that the creation of an accessible international data base could lead to the development of cooperative communication networks between law enforcement agencies and academia. This could potentially improve reporting habits, as well improve detection and apprehension of serial killers.

The Problem With Typologies

The stereotype of a sexually sadistic killer has been in no small measure perpetuated by the typologies used to describe the typical serial killer. Typologies are attempts to describe the patterns by which serial killers go about their business. While they may be used to categorize individual killers, they are usually directed toward the more general task of understanding overall killing patterns among serialists. These efforts to organize and classify serial murder have some major flaws.

Creating Typologies

According to Hickey (1991), three assumptions about the core characteristics of serial killers influence the development of typologies: serial killing is psychogenic, the locus of motives is internal, and the reward for killing is psychological. As we noted about the definition of serial murder, these assumptions exclude those serialists who are externally motivated (e.g. hit men, terrorists, politically or religiously motivated killers, and black widows). Many cases do not fit easily into existing categories, or straddle several typologies (Gresswell and Hollin 1994; O'Reilly- Fleming 1996). Typologies overlap and conflict with one another. Some are based on motivation while others are based on psychiatric diagnosis. Still others use the criminal offense, or the crime scene, or the geographical mobility of the offender as the basis for classification (Gresswell and Hollin, 1994; Hickey, 1997; Holmes, 1989). The inevitable conclusion we draw from this is that there is no such thing as a typical serial killer. As a result, classification attempts are misleading and tend to reinforce the stereotypes.

Gresswell and Hollin (1994) claim that situational and random factors must be taken into account. When this is done, typologies begin to look less useful. For example, typologies based on motivation assume that serial killers always act according to a plan. In real life, random, unpredictable environmental factors come into play. For example, David Berkowitz ran away after his first victim screamed and bled. He had not anticipated this and so bought a gun for future attacks (Gresswell and Hollin 1994). Moreover, serial killers may have different motives for different victims. Their motives may change over time, and there may be a progression in the killings (personality degeneration, less and less planning, time between episodes decreases, violence increases) (Gresswell and Hollin, 1994; Holmes, 1989). For example, Dennis Nilsen killed a man in the middle of his killing sequence simply because the man was annoying and in his way (Gresswell and Hollin 1994).

Thus, in order for typologies to be useful, Gresswell and Hollin (1994) claim that they must be flexible enough to account for both psychological and random environmental variables, while also recognizing there is a process to serial killing. To date, no typology is capable of meeting these needs.

Discussion/Conclusion

The stereotype of a sexually sadistic killer has become paradigmatic in scholarly efforts to understand serial killers. Definitions, research methods, and typologies reflect this paradigm. Serialists who do not match the stereotype are excluded on arbitrary grounds. Methodological problems associated with data sources manipulate and distort the findings. Official statistics are plagued by incomplete reporting and inaccurate classification. Leyton (1996:37-38) argues that criminologists have forgotten that ideology is the enemy of science: ”...criminological writings tend to be factious, partisan and combative." The study of violence, in general, has become extraordinarily politicized, with various competing interest groups struggling for positional dominance (Jenkins 1994; Leyton 1996). The structure of the academic enterprise and crude methodological tools are seen as fundamental to the dogmatism that plagues academia.

Even the most elementary scientific notions, such as the basic requirement that there be an intimate connection between data and theory, between observation and conclusion, are now implicitly dismissed as old- fashioned and unnecessary, or at best anti-progressive... Reality is now deemed no longer necessary, a vulgar impediment to the flow of masterful ideology (Leyton 1996:37-38).

Leyton (1996) advises scholars to abandon academic ‘turf wars,’ remove self-serving politics from ‘science,’ and adopt interdisciplinary tactics to more fully understand the serial killer phenomenon. Lion (1991) adds that human violence originates from diverse etiologies, ranging from the organic to the functional.

An expanded definition of serial killers, improved reliability of information sources and research methodologies, information sharing, and eradication of the lust killer stereotype will contribute to an enriched understanding. Investing resources in scholarly study can contribute to law enforcement efforts to understand the lust killer stereotype, overcome linkage blindness, and facilitate a paradigm shift (Egger 1990b). These changes are essential if policy decisions and intervention strategies are to be informed by a reliable empirical data.

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Endnotes

1. Egger (1984; 1986; 1988) has revised the definition several times. The essential elements of the definition, however, have remained consistent.