Файл: [D._Kim_Rossmo]_Geographic_Profiling(BookFi.org).pdf

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The degree of animal movement of human remains is a function of

corpse size and decomposition, position, degree of burial, presence of cloth-
ing or wrapping, relative size and strength of the scavenger, season, terrain,
topography, and vegetation (Haglund, 1997a). Body movement, often indi-
cated by drag marks or disturbed ground cover, occurs in stages between rest
places or food caches; these locations may be marked by discoloration from
body fluid seepage. Larger animals, able to drag an entire human corpse,
often move it some distance before covering it with debris or burying it in
a shallow grave. Heavily gnawed or chewed bones are likely to have been first
carried off from the original body location.

Skeletal remains are usually found within 100 metres of the primary

deposition site, but some pieces may be dragged as far away as 300 metres
(Haglund, 1997a). Evidence is most likely located along animal trails and
paths between primary body deposition and other recovery sites, but these
trajectories might not be straight because of interim rest sites (Keppel &
Birnes, 1995). Terrain, inclines, and sedimentation also influence the scatter
pattern (Haglund, 1997b).

Teeth and bone fragments are often found in animal scats; their analysis

can assist in species identification and determination of animal territory and
movement patterns. Coyote ranges vary from an average of 3.2 kilometres in
forested areas to 16.1 kilometres in open landscapes (Haglund, 1997a).
Understanding faunal activity is an important step in establishing the evi-
dence search area (Murad, 1997).

8.1.6 Learning and Displacement

The criminal hunt is influenced by both internal and external factors. Serial
offenders gain knowledge with each new crime and they often learn from
their experiences, successes, and failures, avoiding mistakes and repeating
successful tactics (Cusson, 1993; Warren et al., 1995). Criminal development
also results from education, changes in lifestyle, increased “professionalism,”
new associates, and disorder progression. Media disclosures and certain
investigative strategies, particularly patrol saturation tactics, may create spa-
tial and temporal displacement, altering the geographic behaviour of the
offender to the point that apprehension is hindered or delayed.

After the media reported fibre evidence had been recovered from victims’

bodies during the investigation of the Atlanta Child Murders, Wayne Williams
changed his dumping grounds from remote roads and wooded areas to local
rivers (Douglas & Olshaker, 1995; Glover & Witham, 1989). By disposing of
unclothed bodies in this fashion he hoped that any physical evidence would
be washed off by the water. The geography of Atlanta’s rivers is markedly
different from that of its roads and woods, therefore this change in M.O. led
to a shift in the geographic pattern of the crime sites (see Dettlinger & Prugh,

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1983). After the publication by the 

Victoria Times-Colonist

 of an unofficial

profile on a dangerous serial arsonist in which a psychologist stated the
offender was operating in his own neighbourhood, Manley Eng targeted a
building on the other side of Saanich, British Columbia, removed from all
his previous fires. And when New York papers wondered if the Son of Sam
would continue his pattern and strike in each of the City’s boroughs, David
Berkowitz responded accordingly (Ressler & Shachtman, 1992).

Displacement is a change in an offender’s pattern of behaviour as the

result of crime prevention efforts, community wariness, or police investi-
gative strategies. While displacement is by no means a certain result, it is
more likely to occur with strongly motivated criminals such as sex offend-
ers. There are five possible outcomes of displacement typically discussed
in the literature: (1) spatial (geographic or territorial); (2) temporal; (3)
target; (4) tactical; and (5) functional (activity) (Reppetto, 1976). Spatial
displacement is the main concern for geographic profiling, but the other
forms of displacement can also alter target patterns because of victim back-
cloth influences. Davies & Dale (1995b) found evidence for spatial, temporal,
and tactical displacement in their study of British serial rapists.

Geographic or spatial displacement results when an offender relocates

his or her criminal activity in response to a perceived increase in the risk of
apprehension or reduction in opportunity (Gabor, 1978; Lowman, 1986).
This geographic shift can be on a neighbourhood, metropolitan, or regional
scale. Spatial displacement also involves a change in the type of place targeted
within the same general area (e.g., from a downtown prostitution stroll to a
downtown nightclub district). Some offenders move of their own accord and
commit crimes in a new neighbourhood, but this is not characterized as
displacement because the change resulted from something other than police
or community action.

Temporal displacement results when an offender shifts his or her criminal

activity to a different time period in response to a perceived modification in
risk or opportunity environments. The shift is to a period (e.g., time of day,
day of week, etc.) when acceptable risk and target availability levels exist.
This may involve an extended period of offender inactivity, ranging from
weeks to years, known as remission. Remission can also result from episodic
behaviour on the part of the offender; in such cases, the temporal patterning
of the crimes is the result of internal psychological factors, and not external
influences. It is not uncommon for a criminal to appear to have gone into
remission, when in reality he or she has only moved to another area —
perhaps as the result of spatial displacement. Communication difficulties and
linkage blindness then prevent the crimes in the new jurisdiction from being
linked to the previous ones.

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Target displacement occurs when an offender modifies the selection of

premises, objects, or subjects as targets for his or her criminal activities. This
may result from such activities as target hardening or community awareness.
A child molester who selects older teenagers after increased vigilance around
elementary schools has engaged in target displacement. Tactical displacement
occurs when an offender uses alternative strategies or changes his or her M.O.
to achieve the same criminal goals. This is usually the result of learning.
Functional or activity displacement results when a different form or type of
criminal behaviour is engaged in by the offender (e.g., a shift to bank robbing
from safe cracking), often resulting from changes in opportunity due to
technology. A rapist who begins to kill his victims strictly to prevent identi-
fication has engaged in functional displacement.

8.1.7 Offender Type

Criminal profiling can assist in determining the relationship between an

offender’s routine activities and his or her target patterns. The FBI dichoto-
mizes repetitive sexual killers into organized and disorganized categories,
based on offender personality and type of crime scene

45

 (Ressler et al., 1988).

These groups are alternatively labelled organized nonsocial and disorganized
asocial offenders. FBI research suggests that organized offenders comprise
48% of the murderer population (both sexual and nonsexual), disorganized
offenders 33%, mixed offenders 14%, and unknown cases 5% (Classifying
sexual homicide crime scenes, 1985).

46

Organized offenders usually plan their crimes, employ restraints, and

attack strangers (Barrett, 1990). Most of the time, they have access to a
serviceable vehicle and are willing to travel great distances. Organized offend-
ers are more likely to expand the boundaries of their awareness space and
hunt in areas located further from home. They are typically mobile murder-
ers, often transporting victims to the murder site and then hiding their bodies
(Ressler & Shachtman, 1992). In research of British child sexual murderers,
Aitken et al. (1994) found that evidence of travel or victim abduction was

45 

A profile will indirectly infer organized or disorganized personality types from evidence

and signs left by the offender at the crime scene (Crime scene and profile characteristics
of organized and disorganized murderers, 1985). “Profilers pay particular attention to the
manner in which a person was killed, the kind of weapon that was used ... If the killer
brought along his own weapon, it points to a stalker, someone fairly well organized, even
cunning, who came from another part of town and probably drove a car. If the killer used
whatever weapon was available — a knife from the kitchen or a lamp cord — it points to
a more impulsive act, a more disorganized personality. It also means that the person
probably came on foot and lives nearby” (Porter, 1983, p. 47).

46 

By comparison, the FBI study of 36 sexual murderers classified 62% as organized, 25%

as disorganized, and 13% as mixed; or, alternatively, 44% very organized, 19% organized,
6% mixed, 14% disorganized, and 17% very disorganized (Ressler, 1989).

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indicative of journey-to-crime distances greater than 5 miles. Organized
murderers follow their crimes in the news and may move or change jobs to
avoid apprehension (Ressler et al., 1988).

Disorganized offenders may know their victims. They act spontaneously,

and tend to live or work within walking distance of the crime sites, usually with
their parents or in a small apartment. Disorganized killers murder their victims
at or near the encounter site, and often leave the body in plain view at the murder
scene. They often choose crime sites from familiar areas and strike close to the
nodes and routes of their activity space. The awareness space of the disorganized
criminal is likely to be smaller and less complex than that of the organized
offender. Disorganized offenders are not concerned about the media, and are
unlikely to significantly change their lifestyle to avoid apprehension.

8.2 Hunting Methods

Throughout accounts of serial murders run themes of adventurous risk in
the stalking of human prey by stealth or deception, the excitement of the
kill ... The egoism of the hunter permits the degradation of potential victims
to the level of wild game. The planning, excitement, and thrill of the hunt
overrides all other considerations except eluding capture. 

– Green, 1993, pp. 143, 147

Serial violent criminals are predators — they search for human victims

in manners similar to carnivores hunting for animal prey. And like wildlife,
they employ various hunting styles in their efforts to seek out and attack
victims. Target patterns are determined by offender activity, victim location,
environment, and situational cues. Any analysis of the criminal hunt must
consider these factors.

8.2.1 Target Cues

In a study of active urban burglars in Texas, Cromwell, Olson, and Avary
(1990, 1991) found environmental and target cues played key roles in offender
assessment of risk, effort, and gain. The burglars first determined if a premise
was occupied using various external visual indicators. If the place appeared
uninhabited, they assessed its surveillability (from neighbouring homes), and
then its accessibility (usually from the side or rear). These burglars were
looking for satisfactory, not optimal target choices. Offenders influenced by
drugs or alcohol viewed targets as more vulnerable and crime as less risky.

Burglars search for their targets along obvious routes (Cusson, 1993),

and Cromwell et al. (1990, 1991) found routine activity variables to be useful

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predictors of break-ins. Corner location, average traffic speed, proximity to
schools, businesses, parks, churches, stop signs, traffic lights, four-lane
streets, and the presence of a carport or absence of a garage were all signif-
icantly related to burglary risk. Corner homes, premises situated along streets
with slower traffic, and places close to stop signs or traffic lights are more
likely to be noticed by scouting burglars. Homes with carports or without
garages allow occupancy to easily be assessed from vehicle presence. The time
patterns of these criminals were determined by the time patterns of their
victims. “The typical burglar is much more aware of our use of time than
we are” (p. 59).

In a study of active burglars in St. Louis, Missouri, Wright and Decker

(1996) observed that offenders found burglary sites in one of three ways: (1)
through prior knowledge of the victim; (2) by obtainment of inside infor-
mation; or (3) most commonly, by observation of potential targets. The third
method provides insight to how certain violent criminal predators behave.

Typically, the choice of a house to break into is not spontaneous; instead,

the groundwork has been done, possible targets lined up, and preliminary
information collected. Offenders wish to determine potential risks and
rewards before committing a break and enter. “‘I look at a house two or three
times before I go in it’” (Wright & Decker, 1996, pp. 41–42). Burglars are
attracted by certain external “reward and risk” cues that allow them to make
inferences regarding the occupants and contents of the house (a process that
also leads some offenders to transfer responsibility for the crime to the target,
claiming that the house was “just asking for it”). They had some knowledge
of the occupants’ routines, and noted such things as the number, presence,
and absence of vehicles.

Wright and Decker (1996) considered how burglars locate their residen-

tial targets:

But how do offenders come to be watching those places to begin with? Do
they purposely seek them out? Or do they simply stumble on them in the
course of their daily rounds? For most of the offenders in our sample who
typically watched dwellings before breaking in to them, the answer seemed
to fall somewhere between these two extremes. The subjects usually did not
go out with the specific intention of looking for potential targets. Nor did
they generally just happen upon places when locating prospective burglary
sites was the last thing on their minds. Rather they were continually “half
looking” for targets … “I might go to the neighborhood park or something
and then I might say, ‘Well, I’m a go home this way today.’ Then while I’m
walkin’ up the street I just be lookin’, checkin’ it out.” (pp. 42–43)

Targets were usually found by offenders attuned to their surroundings

during the course of their daily routine activities, and then intermittently