Saturday, February 2, 2013

Sex offenders are on the move

(Part) FACTOID & (Part) TRUTH:
Even though there are several problems within this study (see highlights below), it does show that a significant number of registrants are moving. Given that fact, one would think the study authors would want to know why, but they ignore that and draw conclusions based on, yet undetermined, not apparent in the study! While the technology used to record movement is valid, it must also include all the facts before drawing conclusions, here missing!
January 2013:

Geospatial technologies help track real-time movements of sex offenders

Convicted sex offenders continue to move freely within communities, including in restricted areas, despite laws designed to limit their movements. A new study, by Alan Murray from Arizona State University and colleagues, uses new tracking techniques to better understand the actual movements of sex offenders. This information can help develop effective strategies to promote public safety. The findings are published in a new book, Crime Modeling and Mapping Using Geospatial Technologies, published by Springer.

Sexual offenses, especially those committed against children, are of concern to both the public and policy makers. In response to these concerns, local, state and federal legislators in the US have passed a series of laws designed to reduce interaction between children and these potentially dangerous individuals. To date, the vast majority of research on sex offenders and residence restrictions deals with issues of housing availability and affordability. Very little work has focused on sex offender mobility, and residence trends in particular.

Murray and his team analyze sex offender residential movement patterns over a two and a half year period in Hamilton County, Ohio.  They used geographic information systems and a developed exploratory system (SOSTAT)* to uncover spatial behavioral patterns, which give important insights into offender reintegration, their mobility within communities and the implications of restrictions on both offenders and the community.

Their analyses showed that sex offenders appear to be a very mobile group. Over the two and a half year period, 65 percent of registered offenders changed residences. Although there was a noticeable trend towards fewer offenders living in restricted zones overall, worryingly, nearly a third moved from non-restricted areas into restricted zones.
The first flaw in this study is, authors ignore why there is movement? Authors simply make conclusions. Interestingly is, if 1/3 moved into restricted zones, in reality they would have been arrested. So what is the authors' definition of "restricted zones," were those zones actually covered by a local law? Did the authors arbitrarily create zones they believed should be covered by a law? Are the police not arresting registrants if they move into a restricted area -covered by a law-? All questions unanswered by the authors!
The authors conclude: "Over the years, changes in laws governing post-release activities of offenders were designed to monitor and track this group of individuals. Our study highlights that, despite these increasingly stringent laws, sex offenders move freely about communities and continue to reside in restricted residential areas. This mobility suggests that current policies may require modification to achieve their intended goals."
It appears these authors believe, that the purpose of registries is to prevent registrants from moving into any community. History has shown that the purpose of registries is, simply to know where registrants live in communities, not to prevent them from moving into communities, or from moving when they have a reason to do so (Often because of harassment or newly enacted laws [Remember, authors ignored looking at why registrants move])!
This example of the value of spatial analysis for crime analysis is featured in a new book Crime Modeling and Mapping Using Geospatial Technologies edited by Michael Leitner of Louisiana State University in Baton Rouge (USA). The book tackles various types of crime and places them in a geospatial context. As well as posing interesting questions on crime in such a context, the chapters also discuss applications and implementations of geographic information systems.

*Key components of SOSTAT include a map-based display, linked graphics, statistical measures and optimization models. ..Source.. by Springer