This study examined spatial and temporal features
of crime guns in Pittsburgh, Pennsylvania, in order to see how gun
availability actually affected criminal behavior among youth, whether
the effects differed between young adults and juveniles, and whether
that relationship changed over time. Rather than investigating the
general prevalence of guns, this study focused only on those firearms
used in the commission of crimes. Crime guns were defined
specifically as those used in murders, assaults, robberies, weapons
offenses, and drug offenses. Guns that came into temporary police
custody for health and safety reasons were not included in this
study. The researchers focused on just one city in order to explore
the gun-crime connection in rich detail, including variations across
neighborhoods within a city. The emphasis of the project was on the
attributes of crime guns and those who possess them, the geographic
sources of those guns, the distribution of crime guns over
neighborhoods in a city, and the relationship between the prevalence
of crime guns and the incidence of homicide.
Data for Part 1 came from the City of Pittsburgh
Bureau of Police. The Pittsburgh police have traced all guns
recovered by police through the Pennsylvania State Police and the NTC
since the formation of a local firearm tracking unit in early
1994. The gun trace data originating from the Pittsburgh police
provided a detailed view of crime guns recovered by police during a
two-year period, from 1995 to 1997. These data identified the original
source of each crime gun, as well as attributes of the gun and the
person possessing the gun at the time of the precipitating crime, and
the geographic location where the gun was recovered. For Part 2, data
were gathered from the local county crime laboratory on guns submitted
by the Pittsburgh police for forensic testing. These data were from
1993 to 1998 and provided a longer time series for examining changes
in crime guns over time than the data in Part 1. Unlike the trace
data, these data do not include any information about the source of
the gun or attributes of the person who possessed the gun. More
importantly, the two sources provided information on different aspects
of guns. Data on the geographic locations where crime guns were
recovered and their sources were available only for traced guns. The
crime lab data, by contrast, were available for a longer time period
(five years) than trace data (two years). The extent to which the two
sources agreed with one another on the information that they shared
provided some assurance about the validity of inferences derived from
just a single source when the data did not overlap. In Parts 3 and 4,
data on stolen guns came from the local police. These data included
the attributes of the gun and residential neighborhoods of
owners. Part 3 contains data from 1987 to 1996 organized by ZIP code,
whereas Part 4 contains data from 1993 to 1996 organized by census
tract. Part 5 contains the final indicator of crime gun prevalence for
this study, which was 911 calls of incidents involving shots
fired. These data provided vital information on both the geographic
location and timing of these incidents. Shots-fired incidents not only
captured varying levels of access to crime guns, but also variations
in the willingness to actually use crime guns in a criminal
manner. Part 6 contains homicide data for the city of Pittsburgh from
1990 to 1995. These data were used to examine the relationship between
varying levels of crime gun prevalence and the risk of homicide,
especially youth homicide, in the same city. It was expected that
homicides involving youthful participants, especially youthful gang
members, would be especially sensitive to changes in the prevalence of
crime guns. Part 7 is a pilot application illustrating the potential
uses of mapping tools in police investigations of crime guns traced
back to original points of sale. It consists of two ArcView 3.1
project files and 90 supporting data and mapping files.
Parts 1-5 and 7: Guns used in the commission of crime in
Pittsburgh, Pennsylvania, between 1987 and 1998. Part 6: Homicide
victims in Pittsburgh, Pennsylvania, between 1990 and 1995.
Parts 1-5 and 7: Crime guns. Part 6: Homicide
victims.
Parts 1 and 7: United States Bureau of Alcohol,
Tobacco, and Firearms. National Tracing Center. Part 2: County crime
laboratory. Parts 3-6: Pittsburgh Bureau of Police
Variables in Part 1 include date of manufacture and
sale of the crime gun, weapon type, gun model, caliber, firing
mechanism, dealer ZIP-code location, recovery date and ZIP-code
location, age and state of residence of purchaser and possessor, and
possessor role. Part 2 also contains gun type and model, as well as
gun make, precipitating offense, police zone submitting the gun, and
year the gun was submitted to the crime lab. Variables in Parts 3 and
4 include month and year gun was stolen, gun type, make, and caliber,
and neighborhood of owner's residence. Part 3 contains owner ZIP code,
and Part 4 contains census tract number and neighborhood name. Part 5
contains the date, time, and census tract of 911 calls relating to
shots fired. Part 6 contains the date and census tract of the homicide
incident, drug involvement, gang involvement, weapon, and victim and
offender ages. Data in Part 7 include state, county, and ZIP code of
traced guns, population figures, and counts of crime guns recovered at
various geographic locations (states, counties, and ZIP code) where
the traced guns first originated in sales by a Federal Firearms
Licensee (FFL) to a non-FFL individual.
Not applicable.
None.
Hide