Electronic Tether

Chamberlin was back in jail last fall -- he has served time for four similar offenses since 1998 -- after a GPS device attached to his ankle revealed that Chamberlin violated his parole by coming within 100 feet of a Southern California high school and spending time on campus at University of Redlands.

California's two-year, state-sponsored GPS program began in July 2005, and is among several initiatives around the country using satellite monitoring technology to track convicted sex offenders. It's a movement that picked up steam after pedophile John Couey kidnapped, raped and killed 9-year-old Jessica Lunsford in Florida.

Couey was a convicted sex offender, and was required to register as such by Florida law and provide a current address. He didn't. And in essence, he was free to roam northern Florida and attack Lunsford. Police finally located him in Georgia a month after the abduction.

The episode, and the resulting fallout, prompted the Florida Legislature and Gov. Jeb Bush to pass the Jessica Lunsford Act, a law that increased sentences and authorized the spending of about $7 million to cover the mandatory GPS monitoring of sex offenders.

It turned out that Couey was among about 1,800 of the 30,000 or so registered sex offenders in the state who failed to provide location information to the state as required, and have essentially vanished, according to a Miami Herald report.

And the problem is not unique to Florida.

Information Control

John LaFond, recently retired law professor from the University of Missouri-Kansas City, and author of the book Preventing Sexual Violence, said states generally deal with sex offenders in one of two ways: sentencing a first- or second-time offender to long prison terms, or releasing them after a shorter sentence with few requirements. The latter is the prevailing choice, because of cost and because society has decided the majority of these offenders deserve a second chance.

"We subject them to what I call 'information control,'" LaFond said. "They may have to register and we may give notification to the community that they're there, but for the most part, the state washes its hands of any duty to effectively monitor dangerous sex offenders in the community."

Most states require sex offenders to register, but LaFond said the registration of sex offenders is a hit-or-miss proposition because it does nothing to keep track of offenders if they want to disappear, and it's replete with errors. An offender will often move, and his former address, now occupied by somebody else, remains listed as the home of a sex offender. In addition, at least 20 percent of sex offenders don't register, according to LaFond and former Utah CIO Phil Windley.

"We're not really tracking the person," Windley said. "We're tracking the location."

That leaves GPS monitoring as the latest, promising tool against the perceived dangers, according to Kim English, director of Colorado's Office of Research and Statistics within the Division of Criminal Justice.

"What happens with sex offenders is there's a new solution to the problem about every six months," English said. "It's community notification; it's law enforcement registration; it's DNA testing; and right now, it's GPS monitoring."

Missouri, Ohio, Oklahoma, California, Colorado and Florida are deploying GPS technology as part of a strategy to better monitor sex offenders.

Florida has used GPS monitoring of parolees (not just sex offenders) since 1998, but has now taken on the task of monitoring some sex offenders for life.

The GPS devices are generally two-piece