The crime analyst for the San Diego County District Attorney's Office describes her work with experts in geographic information systems (GISs) in using mapping and spatial analysis as means of determining the effects of sex offender residency restrictions if California's Proposition 83, called Jessica's Law, was to pass.
Proposition 83, which was on the California ballot in the fall of 2006, increased penalties for specific sex offenses, stipulated that all sex offenders had to wear global positioning system (GPS) anklets, and created a 2,000-foot residency restriction for all sex offenders around schools and parks where children "regularly gather." The author of this article was asked to create a variety of maps and spatial analyses in order to educate policymakers, law enforcement agencies, and community organizations about the effects of Jessica's Law if it passed. The author, working with a team of GIS experts, determined the percentage of registered sex offenders currently living in zones that would be excluded as areas where sex offenders could reside. They also identified those areas where sex offenders would be allowed to live in the county. The analysis found that much of the "available" land was open space or other nonresidential property, so the analysts added land-use and tax-parcel data in creating a better estimate of the actual land available for sex-offender residency. The results of the analysis were made public, including presentation of a series of maps that showed the areas that would and would not be available for sex offender residency if Jessica's Law was to go into effect. 9 notes