My only concerns was being prepared ... Some Saturdays and Sundays I drove along the Coast, not looking for hitch-hikers, just searching out places. On back-waters of the Pee-Dee River, near where I had worked with the cypress cutting and hauling crews, I found old logging roads that went for miles into the swamps — and more trails into marshes south of Georgetown

... I decided on spots I could get to quick from main Highways, but far enough away so I wouldn’t have to worry about anybody seeing or hearing, and I always picked spots that had a nice burying place close by.

—Donald “Pee Wee” Gaskins, planning his South Carolina coastal kills; Gaskins & Earle, 1993, p. 123

9.1 Spatial Typologies

Most research and commentary on the geography of serial murder and violent crime has been descriptive, aimed primarily at the classification of spatial patterns of crime scenes. This is an important prerequisite for understanding the methods used by predatory criminals during their hunt and the resulting geography of their crimes. It is from this basis that efforts to geographically profile violent offenders can begin. These typologies typically analyze such factors as victim selection, offender hunt, crime pattern, mobility, distance, and method of body disposal.

Holmes and De Burger (1988; see also Falk, 1990) categorize serial murder location patterns as: (1) concentrated (characteristic of the visionary, missionoriented, hedonistic lust, and hedonistic comfort serial murderer types); or

(2) dispersed (characteristic of the hedonistic thrill, and power/control-ori- ented serial murderer types). Thus serial killers are: (1) geographically stable (concentrated target patterns); (2) geographically transient (dispersed target

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patterns); or (3) mixed (a combination of stable and transient). The motives of geographically stable serial killers are often sexual in nature, and their victims specifically selected. Transportation of the victim’s body is a crime scene characteristic associated with the lust, thrill, and power/control-oriented serial murderer types (Holmes & Holmes, 1996).

Robbins (1991) researched differences in the methods and motives of geographically stable and geographically transient serial murderers. In a study of 20 well-known recent (1970 to 1991) convicted and incarcerated male serial killers, she found geographically stable serial murderers typically operate in areas occupied by members of their own race, seek specific victim traits, are organized, and plan their crimes in advance. They tend to be thrill oriented and young, and often commit their crimes under the influence of alcohol or drugs. These killers have been known to engage in necrophilia and decapitate their victims for the purposes of delaying identification. Body dump sites are different from murder scenes, necessitating transportation of the victim’s body; both locations are chosen by the killer ahead of time.48 Usually victims are left clothed and their remains are discovered.

Geographically transient serial murderers, by comparison, are more likely to have a history of sexual abuse in their backgrounds, tend to be less organized, and have shorter attention spans (Robbins, 1991). This typically results in a lower level of formal education, more marital breakdowns, and a record of working odd jobs. These killers often travel extensively and have a propensity for not staying long in one place. They are less victim specific and ritualistic in their crimes, often changing choice of weapon and method of operation. They are older, oriented towards power and control, and more frequently engage in biting and cannibalism (see Wilson, 1988). Usually victims are left unclothed and their remains are less likely to be discovered.

Table 9.1 summarizes the target pattern characteristics associated with various categories in the Holmes and De Burger serial murderer typology (including Barrett’s opportunist serial killer type) (Barrett, 1990; Holmes & De Burger, 1988; Holmes & Holmes, 1996; Robbins, 1991).

In a study of 28 convicted serial sex murderers who targeted female victims, James (1991) noted various offender characteristics related to hunting behaviour and crime site geography. He recorded the following data on victim selection, hunting behaviour, offender transportation, attack, body disposal, and apprehension:

48 Dietz et al. (1990) found 93.3% (28) of the sexually sadistic criminals they studied carefully planned their offences, 76.7% (23) took victims to a preselected location, and 60% (18) kept at least one victim captive for 24 hours or more (see, for example, Gaskins & Earle, 1993). Cases of extended captivity indicate an offender with access to a safe and secure place in which to hold the victim (Ressler & Shachtman, 1992).

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3.Transportation

•78% used vehicles, either directly or indirectly, in the commission of their crimes;

•50% of those who directly used vehicles in their crimes offered their victims rides;

•54% drove their own vehicle, 9% a relative’s, and 18% used a stolen automobile; and

•7% used public transportation, and 4% flew an aircraft.

4.Attack

•75% of the serial murderers conned their victims to gain control, and 68% used a ruse to get them to the attack location;

•21% employed immediate force to gain control; and

•32% attacked on their own property, 29% on the property of a relative or friend, and 29% in the victim’s residence.

5.Body Disposal

•64% tried to conceal their victims’ bodies in remote areas;

•29% buried their victims underground, and 21% dumped them in water; and

•68% moved the bodies of their victims after the murder.

6.Apprehension

•61% had a previous criminal record;

•11% had been observed within the crime area by police, and 18% were connected to the crime area by patrol officers;

•29% had been questioned and then released;

•14% were arrested through surveillance methods, and 8% through patrol work;

•31% were caught as the direct result of police investigation activities, and 61% from witness information; and

•32% kept incriminating evidence at their home or workplace, and 29% on their person or in their vehicle (some murderers did both).

Wingo classifies serial killers as “megastat,” those who kill over time in a single static urban environment, or “megamobile,” those who are mobile and travel over great stretches of geography (Egger, 1990). In their study of sexually sadistic criminals, Dietz et al. (1990) note that 40% of their subjects (n = 12) engaged in “excessive driving” (travelling long distances or with no clear direction). Davies and Dale (1995b) observe many British rapists are incessant prowlers, cruising by vehicle, public transportation, or foot. This finding has been confirmed in both U.S. and Canadian studies, underlining the investigative importance of recording information on prowlers, trespassers, and suspicious persons. Viable sexual assault suspects can often be found through such records when queried by geographic area.

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Mobility, however, does not necessarily translate into range. Keppel (1989) notes “serial killers are highly mobile, frequently cruising and drawn to those victim contact areas where they feel they are in their ‘comfort zone’ ” (p. 65). Such offenders typically have ready access to vehicles which they use to become familiar with their preferred victim encounter and body disposal areas. Keppel cites the examples of Wayne Williams and John Wayne Gacy, Jr., both of whom confined their murderous activities to a single metropolitan area — Atlanta and Chicago, respectively. The mobility associated with serial murderers can result in a higher frequency of cruising, but not necessarily in greater geographic reach.

Hickey (1997) found three geographic categories of offender in his study of serial murder: (1) travelling killers (34%), who commit murder while moving through or relocating to other areas; (2) local killers (52%), who remain within a certain urban area, or a single state; and (3) place-specific killers (14%), who murder within their own home, workplace, or other specific site. Local serial murderers are responsible for fewer victims per offender than travelling or place-specific killers, both of whom are harder to apprehend. Linkage blindness is a significant problem with mobile offenders, and authorities are often not aware that a place-specific murderer is active. Hickey (1990) observes a shift in mobility patterns post-1975, with an increase in local serial killers and a reduction in out-of-state travelling and place-specific offenders. He suggests these shifts may be due to increased urbanization, advances in techniques of forensic analysis, and changes in methods of murder.

Newton (1992) studied 301 U.S. and 56 non-U.S. serial murderers from a 20-year period, and classifies them by hunting style into: (1) territorial killers (63% of U.S., 70% of non-U.S. cases), who stake out a defined area;

(2) nomadic killers (29% of U.S., 15% of non-U.S. cases), who travel widely in their search of victims; and (3) stationary killers (8% of U.S., 15% of non- U.S. cases), who commit their crimes at home or work. Newton notes that serial murderers usually follow the same hunting style, which he feels expresses their view of life and who they are.

These results contradict the generally held assumption that serial killers are highly peripatetic (Egger, 1984; Keppel, 1989). Levin and Fox (1985) found “traveling serial killers ... are a minority to those ... who ‘stay at home’ and at their jobs, killing on a part-time basis” (p. 183). Serial murderers tend to be geographically stable, killing in areas they know. Turf is a valued commodity and Barrett (1990) suggests offenders avoid hunting in areas besieged by other killers, though this might be best explained by the scarcity of the phenomenon. Newton (1992) comments that the majority “rarely deviate from the selected game preserve” (p. 48). Perhaps executed serial murderer Donald “Pee Wee” Gaskins said it best: “I felt safer doing my killing and burying in my home state. I guess I’m just a Carolina Southern-boy at heart” (Gaskins & Earle, 1993, p. 161).

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Serial murder victims are more often attacked outside their home than other homicide victims because of the crime’s stranger nature, and potential victims are more vulnerable in areas where such killers have ready access. Hickey (1997) found female serial child killers are more likely than their male counterparts to be place-specific (33% vs. 13%), and male serial child killers more likely to be travellers (46% vs. 21%). This result reflects the institutional nature of the locations involved (e.g., hospitals, boarding houses, etc.) involved. Most employed female serial murderers use their occupational position to access victims (Scott, 1992; Segrave, 1992).

In their study of serial rape in England, Canter and Larkin (1993) applied the circle hypothesis as a means of dividing offenders into “marauders” or “commuters.” An offence circle is the region enclosed by the circumference of the circle, the diameter of which is the line joining the two most distant crimes. Marauders are individuals whose residences act as the focus of their crimes. Commuters, on the other hand, travel from home into another area to commit their offences. The circle hypothesis suggests that marauders reside within their offence circle, and commuters reside without. Only 13% of the British serial rapists (n=45) had a home base outside of their offence circle. Finding little support for the commuter hypothesis, the research concluded that rapists, like most people, are typically “domocentric.”

Kocsis and Irwin (1997) caution, however, that the generality of this conclusion is doubtful. In a study of Australian serial offenders, they noted that 71% of rapists, 82% of arsonists, and 48% of burglars resided within their offence circle. The FBI found 51% of U.S. serial rapists (n = 76) lived outside of their offence circle, and 76% outside of the convex hull polygon (see above) created by their crime site pattern (Warren et al., 1995). Alston (1994) had similar results to those of the FBI in his study of 30 British Columbia stranger sexual assault series; in 43.4% of the cases the offence circle did not contain an offender activity node. National differences in urban structure, neighbourhood density, and travel behaviour might contribute to the inconsistencies in these findings (Warren et al., 1995).

One of the problems with the circle hypothesis is its determination of hunting behaviour solely from the crime site point pattern (see Alston, 1994, for a discussion of other issues of concern). In cases involving large numbers of offences, a rapist may commute to several different areas in various directions, creating an offence circle that contains his residence. And in cases involving small numbers of crimes a marauder might find by chance all of his victims in the same direction, resulting in an offence circle that excludes their home base. Offence circles could therefore lead to both commuter and marauder designations, depending upon what point in a serial rapist’s career they were generated.49 This happened in both the Yorkshire Ripper and the Boston Strangler cases (Burn, 1984; Davies & Dale, 1995a; Frank, 1966). In

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