Statewide Crime Analysis and Mapping Program (SCAMP)
The Massachusetts State Police are in the process of developing a crime analysis viewing environment that will be deployed to local police departments by use of the World Wide Web (WWW). This initiative has been dubbed the Statewide Crime Analysis and Mapping Project (SCAMP). The core information feeding this system will be the National Incident-Based Reporting System (NIBRS) database. Local departments submit formatted NIBRS data to the State Police where they are consolidated into a multi-town database. Currently the State Police are getting NIBRS data from 168 local and campus police agencies, covering a population of over 2.5 million. The goal of this project is to make these data available in a mapping environment where they can be analyzed by local police departments performing crime analysis. The mapping component will enable local departments to look for spatial patterns (i.e., clusters) in incidents as well as conduct regional analysis by looking at patterns in neighboring communities. The Web-based approach will help smaller departments that may not yet have their own Geographic Information System (GIS) capacity attain the benefits of GIS mapping through a simple desktop browser.
The first task in completing a Web development project is performing a preliminary analysis and systems design. To design an effective, database-driven Web site, it is first necessary to understand the details of the existing data structures and the intended purpose for creating the site and identify the details of functionality that the new site must deliver. The crime analysis system will be devised through meetings with State Police staff and outside advisors to the project. Through this process, a "blueprint" for specific development activities will emerge. This blueprint document will outline the overall architecture of the application as well as making explicit the mechanisms and functionality for integration with the NIBRS database on an ongoing basis.
One of the key issues to be addressed at the outset is the formatting of the NIBRS data for Web access. The prototype Web site will not have direct network access to the NIBRS database. Thus, the issue is whether the Web site source data should be direct facsimiles of the State Police Database running on a different machine, or whether the Web site should be driven by formatted copy of information within the database, perhaps optimized for Web site access. Examples of the types of issues that must be examined include:
- Table normalization: copy State police NIBRS model or develop a new GIS/Web friendly model?
- Copy all NIBRS records (700,000) or only records with addresses (80,000)?
- Copy all NIBRS address records or only geocoded records (60,000)?
- Develop a strategy for easily refreshing the Web site source data from the State Police master system since approximately 15,000 new records are added to this database each month.
It is important to identify all spatial data layers that will need to be included in the system. In doing so, graphic data will be included from other databases. Examples of the types of databases that will need to be collected include:
- Statewide roads data layer
- Statewide digital orthophotos
- Statewide town boundaries
- Statewide census geographies and demographics
- Statewide ZIP code boundaries
- Statewide geographic names
- Statewide scanned topographic quadrangles
- Police sector boundaries collected from individual departments with digital data
- Neighborhood boundaries collected from individual towns with digital data
- Parcels collected from towns with digital data
Once the database sources for the applications are properly organized and consolidated, Web site development can take place. A comprehensive, functional Web site will be developed. General characteristics include:
- Secure environment with individual-level username/password protection
- Site usage audit capability including number of users, number of maps/reports by user, and time per session by user
There will be an initial focus on crimes against property mapping/reporting:
- Categorization with differential symbolization of property crimes by robbery, burglary, larceny, and motor vehicle theft
- Tools for rolling up incident data into summary statistics by geographical area
- Facilitate mapping/reporting by querying: date/date-range; time/time-range; location; property type stolen; total value of stolen property
Maps will be based on:
- User-defined buffer around an address
- Neighborhood, patrol sector, census block/blockgroup/tract of interest
- Entire city or town
- Region or group of contiguous towns
- User-defined box
The system will produce a variety of products:
- Products for internal police department use
- Products for external use (policymakers, media, and general public)
- Color maps directly printable from Web browser
- Statistical summaries directly printable from Web browser
Once developed, the Web system will be tested to ensure that the site is stable and provides good performance. Following feedback from State Police, a prototype site will be ready for operational use by the State Police and its selected users.
If you'd like more information on SCAMP, please contact Daniel Bibel (firstname.lastname@example.org), Program Manager of the MA State Police Crime Reporting Unit.