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Spring 2003
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Austin, Texas, Police Department Takes a Bite Out of Burglary With GIS

By Kathleen Woodby, Supervisor, Crime Analysis Unit, and Tess Sherman, Senior Crime Analyst, Austin Police Department

  click to see enlargement
This map depicts an early burglary pattern in the Austin, Texas, area known as "West Campus" near the University of Texas campus.

The power of a picture. The strength of a technology. Combining the two solves crimes. As we have become an increasingly image-driven culture demanding and relying on visual representations of data for decision making, we've turned to more sophisticated methods for extracting the most from the fundamental, the essential from the whole. Or in considering GIS, the old adage, "a picture is worth a thousand words" can be paraphrased as "a map is worth a thousand ideas." In Austin, Texas, in 2002 it was a basic map that served as the catalyst for a deeper analysis and a major tactical operation that ultimately exposed a lucrative fencing outfit active in the center of the city.

The Austin Police Department (APD) consists of 1,361 police officers and more than 650 "nonsworn" personnel who provide public safety services to the city of Austin. APD uses a neighborhood-based, community-policing philosophy grounded in problem solving. For policing purposes, the city is separated into seven geographical Area Commands. Each Area Command is subdivided into 10 to 12 police districts staffed by seven shifts of district officers.

Prior to 1995, the Austin Police Department employed a computer-mapping program that did not have true GIS capability. A statewide auto theft grant afforded the department an opportunity to obtain a fully capable GIS. Several packages were considered, and Esri's ArcView 3.2a was chosen as the finalist. In 1995, ArcView was first employed in the Auto Theft section in a straight pin mapping capacity to see from where in the city of Austin vehicles were being stolen and recovered. With ArcView, relationships between stolen and recovery vehicle locations became evident. It was later used in buffer analyses with auto theft suspect information to uncover relationships between the residences of known auto thieves and vehicle drop-off locations. Transit theft analysis was also accomplished to detect travel time patterns.

This successful use of GIS in the Auto Theft section led the APD to embrace the technology, and additional copies of ArcView were purchased and fielded in the evolving Crime Analysis Unit.

A Case in Point

In April 2002, the crime analyst for the Downtown Area Command (DTAC), using ArcView 3.2a as part of a standard reporting process that includes maps of weekly and monthly criminal activity, noticed a pattern of nonresidential burglaries of churches in a five-block area in DTAC. This prompted a crime alert to be issued to patrol officers in the area. A closer reading of report data revealed a strong pattern that suggested that all hits were occurring overnight and midweek. Officers increased patrols in these areas and talked to church secretaries. Information gained from church employees and analysis of the items stolen pointed to the probability that transient persons were most likely involved.

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Spider Distance Analysis demonstrating centroid of crime events in relationship to loction of egg roll cart fencing operation.
 

Within the next few weeks the predictable pattern fell apart, but the trend of increased burglaries in this area still continued to climb. The "normal" threshold of burglaries within the quarter-mile area was one to two per month. During April 2002, there were five residential and two nonresidential burglaries on Nueces Street alone. Temporal and spatial characteristics indicated a strong link in eight of the 15 burglaries. The DTAC analyst suspected an underlying geographic pattern and rationale from the tight proximity of the burglaries and their heightened frequency. However, a piece was still missing.

The area of these burglaries bordered the University of Texas campus with 15th Street as its southernmost boundary. The concentration of burglaries grew stronger five blocks north of 15th Street and west of Guadalupe Street. Guadalupe Street is the western boundary of the University of Texas campus.

The first break came when the DTAC crime analyst noticed a reference to "the 29th Street boys" in an offense report. A victim in one of the residential burglaries made the statement that he had heard there was a group of homeless persons living in the alleys of 29th Street (the northern border of the University of Texas campus) who were committing car and other burglaries. This information also supported the analyst's belief that transients had committed a series of April church burglaries in DTAC.

The analyst used this additional information in analyzing the pattern. The ArcView Animal Movement extension was used to determine the relationship between the burglaries and the alleys along 29th Street. This confirmed the presence of a clumping pattern through the nearest neighbor analysis. The hypothesis was tested several times throughout the series to determine changes in the pattern.

The specific report mentioning "the 29th Street boys" was not assigned to an investigator because of the lack of a witness and other solvability factors. However, the DTAC crime analyst asked a DTAC detective to see if officers in the field could go to the area and identify the individuals living in this alley for possible fingerprint comparisons to existing cases.

As a result, the neighboring area command (Central West) Street Response Unit did go to the area. They came across two transients who were examining a fishing rod and reel. As they were not close to any body of water, the officers grew suspicious. The officers approached them and eventually learned that they had just stolen the items in a car burglary.

Rather than immediately arresting the two individuals, the officers asked them what they would normally do with such an item, how they would sell it. During this conversation, the men identified the woman running a nearby egg roll/taco cart as their fence. The men agreed to be confidential informants in lieu of arrest, thus setting into motion an investigation that would take six weeks and lead to busting up the largest fencing operation in the history of the city of Austin.

Once the crime analyst learned the location of the fencing operation, the proximity of the offenses to the egg roll stand was mapped. Forty-seven percent of the burglaries during this increased crime trend were within a quarter mile of the fencing operation. She employed the ArcView software's Animal Movement extension again using the Spider Distance Analysis tool. The relationship between three egg roll carts run by the suspect and the locations of the burglaries was still clearly defined. The map visually identified the carts as a convenient location for criminals who are limited to traveling on foot to sell their stolen property in a busy and victim-rich part of the city. Here was the missing piece that explained the sudden rise in area burglaries: an easy access fencing operation that efficiently traded cash and drugs for stolen items while posing as a legitimate Business.

Simply put, nearly all roads led to the egg roll cart.

The next step in the operation involved undercover officers posing as shoplifters and burglars and selling items to the woman running the cart, telling her the items were stolen. These "stolen" items were exchanged for money as well as for a popular prescription pain medication. Surveillance showed a large number of transients coming by regularly and often. There were so many transactions that, as the small carts got full of items, a delivery van would come to pick up the items.

The location of these egg roll carts was in the heart of the University of Texas area known as the Drag, a part of Guadalupe Street that bisects the actual campus from the nearby off-campus student residences, shops, and parking lots. It is also the midpoint between the southernmost border of the burglary activity (15th Street) and the alleys populated by "the 29th Street boys."

On June 19, 2002, four related individuals were arrested for engaging in organized crime during the orchestrated serving of a search warrant that involved more than 50 department employees from four area commands, SWAT, and other units. Three houses were raided, and 395 items were seized along with $62,000 in cash hidden throughout the properties. All of the items "sold" to the suspects by undercover officers were recovered in two of the three houses.

A sampling of items found included 30 calculators, 22 CD players, 21 bags full of assorted clothing, 20 VCRs, 19 drills, 19 watches, 17 cameras, 11 bags of shoes, 11 minicassette recorders, and 10 electric saws.

From the items seized, detectives have thus far only been able to clear eight burglaries. Yet the immediate impact of closing down this fencing operation has appeared to reduce residential burglaries in DTAC by 60 percent since the arrests. Similar reductions in Business burglaries were also seen. Both types of burglaries have returned to their normal ranges since closure of the egg roll stands.

For additional information, contact Kathleen Woodby, Austin Police Department (tel.: 512-974-5255, e-mail: kathleen.woodby@ci.austin.tx.us).

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