Where on earth are sex offenders? States are using satellites to track dangerous sex offenders, many of whom become lost to registration systems.

Global Positioning Satellite technology, developed by the military in the 1960s, is now finding its way into everyday life, for convenience and safety. The U.S. Department of Defense calls the orbiting, solar powered satellites NAVSTAR. States are calling them the latest tool for tracking sex offenders who often disappear from the registration rolls after their release.

In at least a dozen states, policies are pairing intense supervision of sex offenders with constant GPS monitoring of their whereabouts.

JESSICA LUNSFORD ACT 

A 2005 law in Florida spurred by the abduction and murder of 9-year-old Jessica Lunsford in Citrus County, requires lifetime GPS monitoring of certain sex offenders. It contains other provisions to toughen sentencing, enforce the registration requirement, and penalize those who harbor a sex offender in violation of the duty to register, a factor in the Lunsford case.

The transient sex offender who confessed to Jessica's murder had a history of crimes against children. He was required to register under Florida law, but like many others he had failed to keep his address up-to-date for the registry. John Evander Couey held the missing child just yards from her home and the police command center set up to help find her.

"The Jessica Lunsford Act expands on dozens of laws as part of a campaign in Florida to remove these offenders from society," says Representative Dick Kravitz, a sponsor of the act. The law imposes a mandatory sentence of 25 years to life for many offenders who commit crimes against children. Released sexual predators and others who have committed specific sex crimes, particularly those against children, must for the rest of their lives be subject to "active electronic monitoring."

THE COSTS

GPS monitoring costs about $9 a day per offender, according to a fiscal estimate of the act. Staff say costs already are dropping due to the technology becoming more common, as well as economy of scale as the numbers of offenders under surveillance grow.

Conventional house-arrest electronic monitoring, still considerably cheaper, can report if an offender leaves his base location, but cannot identify where he is.

"With active GPS, we'll know more about the movement of sex offenders who need to be watched," Representative Kravitz says. "Are they staying out of excluded areas? Do their movements show unnecessary patterns or deviations? We can know and act on that."

Hoyt Layson Jr., a Florida inventor who adapted GPS for offender supervision and is the chief technologist for Satellite Monitoring and Remote Tracking (SMART), says GPS works to deter crime and identify perpetrators. SMART is the real-time tracking system marketed by the Florida-based company Pro Tech. It's currently in use in Florida, as well as in agencies in Colorado, Kansas and Texas. Florida has had pilot programs using GPS for several years, and found the reoffense rates among those monitored significantly less than would be expected.

"If someone is going to re-offend, let's catch them the first time, not the fiftieth," Layson says. The ability of GPS to help connect possible suspects to a crime is the high tech investigative tool police need, he says. The location of a robbery, for example, can be quickly correlated with offenders known to be in the area at the time of the crime, as well as exclude many others who were not.

"It's a work force multiplier when detectives don't have to spend time scrutinizing the wrong people and can use GPS to focus on the right leads," Layson says.

The technology can also provide all sorts of other information useful to law enforcement. "You can begin to build a density map that tells you where offenders go when they are not at work or school or wherever. You can identify places where offenders co-mingle, and use that information to, for example, check out locations for drug dealing," Layson says.

PROTECTING CIVIL LIBERTIES

In Florida today, there are more than 30,000 registered sex offenders, with nearly 5,500 of them designated sexual predators. As the number of offenders on surveillance grows, so might concerns about protecting civil liberties.

Chris Jay Hoofnagle, a senior counsel with the Electronic Privacy Information Center's (EPIC) San Francisco office, says that policies around "Big Brother" technologies have to look not just at who is being monitored, but also what is being collected, who has access to that information, and how long information is kept and for what purpose.

He says that while GPS monitoring of sex offenders is not something EPIC opposes, it is the kind of thing they watch for "mission creep," or a gradual change in the methods, use and goals of the technology.

"Generally, these things get a foothold by being used on marginalized populations," Hoofnagle says. "Then the march begins to see what else we can do with them."

The Florida Department of Corrections estimates that initially they will monitor about 328 offenders under Jessica's Law. It expects the numbers to triple in the second year and double again in the third year. To Representative Kravitz and others, it's a commitment to policy and funding they are willing to make.

"It empowers law enforcement with tools to do more to protect our communities," Kravitz says. "If these protections had been in place before Jessica Lunsford was killed, that little girl would still be alive today,"

The earth is surrounded by 24 satellites that transmit signals to ground stations. GPS receivers take this information and use it to calculate locations. Once a position has been determined, GPS can make other speed, track and distance determinations. Offenders supervised with GPS wear a wireless anklet device no bigger than a bar of soap requires recharging for just 30 minutes a day. The GPS provides law enforcement with minute-by-minute location information.

Donna Lyons heads NCSL's Criminal Justice Program in the Denver office.