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

© 2000 by CRC Press LLC

shown in 

Figure 10.7

. To successfully conclude the program, the understudy

must pass a qualifying examination at the end of the training period.

The graduate then returns to his or her home agency with the status of

associate geographic profiler. At this stage, he or she is operational and works
active cases, preparing geographic profiles and assessments as appropriate.
The associate is on probation for one year and remains linked to the mentor
for support and guidance. He or she is not allowed to train new candidates
or testify as an expert in court. The associate is also required to conduct a
research project that adds to the body of knowledge in the area of geography
of crime. Upon the successful completion of this component of the program,
the associate becomes a fully qualified geographic profiler. The candidate’s
agency is responsible for all expenses and the mentor’s agency has right of
refusal for unsuitable individuals; a memorandum of understanding is signed
between the two agencies outlining details of the training arrangement. The
qualification process and the candidate’s continuing education are important
for the development of professional skills and expertise (see U.S. Department
of Justice, 1995).

10.4.4 The Rigel Computer System

Rigel

68

 is a computerized geographic profiling workstation based on the pat-

ented CGT algorithm. It incorporates an analytic engine, GIS capability,

Figure 10.7

 Understudy training program.

68 

Rigel

 is pronounced “RI-jul.”

© 2000 by CRC Press LLC

database management, and powerful visualization tools. Crime locations,
which are broken down by type (e.g., victim encounter, murder, and body
dump sites for a homicide), provide the input and are entered by the optional
means of street address, latitude/longitude, or digitization. This reflects the
realities of policing in which crimes can happen anywhere — houses, parking
lots, back alleys, highways, parks, rivers, mountain ravines, and so on. Lati-
tude and longitude coordinates can be determined from a handheld global
positioning system (GPS) that reads the user’s position from a satellite fix.

Scenarios, wherein crime locations are weighted based upon certain the-

oretical and methodological principles, are next created and examined.

69

 Out-

put is a map of the most likely area of offender residence. Suspect addresses
can be evaluated according to their hit score percentage on a 

z

-score histogram,

allowing the prioritization of known criminals, registered sex offenders, task
force tips, and other information. Examples of 

Rigel

 output for a GIS map are

shown in 

Figure 10.2

 and Chapter 10 Colour 

Figures 1

 and 

2

, and examples

for an image map are shown in

 Figure 11.1

, and Chapter 11 Colour 

Figures

1

 and 

2

.

Rigel

 was developed by Environmental Criminology Research Inc. (ECRI)

of Vancouver, British Columbia, and the system currently runs on a high-end
Sun UltraSPARC workstation (a Java-based version was scheduled for com-
pletion in late 1999). This provides the computing power for the 1,000,000
or so calculations of the CGT algorithm a typical analysis requires. Geoprofiles
and jeopardy surfaces can be rotated and visually manipulated in a variety of
ways, facilitating their interpretation. Orthodigital photographs may be over-
laid on the peak geoprofile area, assisting the user in viewing land use within
the region of interest. Large databases can be searched and their entries pri-
oritized by address. These include sex offender registries, major case manage-
ment programs, and crime linkage systems, such as ViCLAS. 

Rigel

 is designed

to enable law enforcement agencies to make the best use of their limited
resources. It is the main tool used in geographic profiling.

Its namesake Rigel (

β

 Orionis) is a supergiant forming part of the winter

constellation Orion (Menzel & Pasachoff, 1983). It is a hot blue star, 50,000
times as bright as our Sun, and 1400 light years away. Rigel, meaning “foot”
in Arabic, constitutes the heel of Orion. In Greek mythology, Orion was a
mighty giant hunter who was loved by Artemis, the goddess of the moon
and hunt; but she was tricked by her twin brother, Apollo, into shooting him
with an arrow. In her sorrow Artemis placed Orion in the night sky with his
hunting dogs, facing Taurus, the bull. Legend holds that her grief is why the
Moon looks so sad and cold (Levy, 1994). The symbolism in the name 

Rigel

70

69 

Expert system support to structure this process and guide the profiler is planned for the

near future.

70 

Orion

 was the name of the software prototype.

© 2000 by CRC Press LLC

for the CGT-based geographic profiling software originates from the idea
that the system is designed to support the hunter — the police detective —
in his or her efforts to apprehend criminal offenders, just as Rigel the star
supports Orion, the constellation hunter.

© 2000 by CRC Press LLC

Investigative Applications

11.1 Strategies and Tactics

A variety of police strategies and tactics can be used more effectively and
efficiently with a geographic profile. While specific applications are best
determined by the investigators responsible for the case in question, sugges-
tions for effective approaches are presented below. Their development has
been an interactive process involving detectives, profilers, and academics.
Case examples are used to illustrate these strategies, but it should be made
clear that the crimes were not solved by geographic profiling; they were
resolved by the assigned investigators. Profiling plays a support role, the
importance of which can vary, and it is only one of many techniques in the
investigator’s tool box.

While the most common anchor point is the offender’s residence, some

cases involve other bases of criminal activity. Clifford Olson used body dump
locations near Agassiz Mountain Prison where he had once been incarcerated.
John Collins hunted in the area around Eastern Michigan University where
he was a student and summer employee. Aileen Wuornos based her “hitch-
hooking” from truck stops and freeway entrances in the town of Wildwood.
Inmate records, enrollment and employee registries, and field checks were
all potentially useful sources of investigative information in these cases. As
important as residence is in structuring activity space, the value of business
and institutional records should not be overlooked.

11.1.1 Suspect Prioritization

The geographic profile, in conjunction with a psychological profile, can help
focus follow-up investigative work. The problem in many serial violent crime
investigations is one of too many suspects rather than one of too few. Profiling

11

© 2000 by CRC Press LLC

can help reassess and prioritize hundreds or even thousands of suspects,
leads, and tips.

The South Side Rapist in Lafayette, Louisiana, committed a series of 14

burglary rapes from 1984 to 1995. Detective McCullan Gallien refused to close
the file, and requested a geographic profile which resulted in the identification
of a neighborhood previously not considered. This was used as the basis for
suspect and tip prioritization. One tip involved a sergeant with the Lafayette
Parish Sheriff ’s Department who both fit the FBI’s psychological profile and
lived in the peak area of the geoprofile at the time of the crimes. DNA obtained
from surveillance of the suspect matched samples from the crime scenes. The
offender confessed, pled guilty, and was sentenced to life in prison. The
geoprofile located the rapist’s address in the top 2.2% (0.5 mi

2

) of the hunting

area. 

Figure 11.1

 and Chapter 11 Colour 

Figures 1

 and 

2

 show, respectively,

the crime sites, jeopardy surface (top 20%), and geoprofile (top 15%) for this
case. Residences of the offender are marked with blue dots in Colour 

Figure

2

; his home during the main period of the attacks was the centre dot.

11.1.2 Police Information Systems

Additional investigative leads may be obtained from information contained
in various computerized police dispatch and record systems. Such systems
include computer aided dispatch (CAD) systems, records management sys-
tems (RMS), the RCMP Police Information Retrieval System (PIRS), and the
like (Fowler, 1990; Rebscher & Rohrer, 1991). Offender profile details and
case specifics can help further focus the search.

For example, police may be investigating a series of sexual assaults that

have been psychologically profiled as the crimes of an anger retaliatory rapist.
Such an offender is “getting even with women for real or imagined wrongs ...
the attack is an emotional outburst that is predicated on anger” (Hazelwood,
1995, p. 163). His rapes are often initiated by conflicts with a significant woman
in his life and he will frequently select victims who symbolize the source of
that conflict. A search of CAD data for domestic disturbance calls on the dates
of the rapes to see which ones originated from the area where the geographic
profile suggests that the offender most likely resides could produce viable
suspects. This process is particularly powerful with police record systems inte-
grated with geographic information systems.

Police agencies with computerized records containing description,

address, and M.O. of local offenders can also use profiling information,
including probable area of residence, as the basis for developing search cri-
teria. Many departments have such files for specific types of criminals, such
as parolees or sex offenders (Brahan, Valcour, & Shevel, 1994; Pilant, 1994;
Skogan & Antunes, 1979). The latter commonly have nuisance crimes (e.g.,