Click image for enlargement. Click image for enlargement. Click image for enlargement. This is a partial view of a Web page showing Tier 3 convicted sex offenders who reside in Henderson. The page is under the police department link for the city Web site, www.cityofhenderson.com.

The kidnapping of two young Idaho children strikes fear in parents everywhere.

The man charged in the kidnapping of a brother and sister, 9 and 8 years old, is a convicted sex offender. He was charged earlier this year with molesting a 6-year-old boy in Minnesota, then released on $15,000 bond despite the prior crime. Police in North Dakota, where the offender lived, had been looking for him since May, when he failed to contact probation officials.

A registry of sex offenders will never help parents protect their children against first-time offenders, offenders who don't have a conviction, offenders who fail to register with authorities where they live or offenders who travel far from their registered address.

But the Nevada Sex Offender Registry -- online at www.nvsexoffenders.gov -- is one tool for families who want to learn, at least, which convicted offenders are known to frequent their neighborhood. The state's Department of Public Safety runs the site, which started up in 2004.

If all of the registered sex offenders in urban Clark County who are listed on the site were evenly divided among its 47 urban ZIP codes, each ZIP code would have 23 offenders, according to data collected in early July. The way it plays out in reality, two central codes -- 89101 and 89030 -- each had more than 100 sex offenders registered. Several ZIP codes had zero or one offender registered.

At that time, the site listed 1,084 offenders for the 47 ZIP codes. That's about 68 percent of the state's total on the site: about 1,600. The tally is constantly changing. "There are always new ones coming on, old ones dropping off," explained Maj. Bob Wideman, head of the Nevada Department of Public Safety.

The Web site is part of a larger sex crime database used by Nevada law enforcement. It displays only offenders who pose the greatest risk; others assessed as a lesser risk must still register, but the Web site doesn't identify them to the general public.

Four tiers of offenders exist under the law, but only offenders in the top two tiers, Tier 3 and Tier 2 -- whose offenses are more numerous or severe, or involved the use of violence -- appear on the site. Currently, the site lists only certain Tier 2 offenders, but Wideman noted that new state law requires it to list all Tier 2 offenders by July 2006.

The Nevada site is not limited to people who have molested children.

"Some are pedophiles, and that's the people we are most concerned with. We also are concerned about any violent sex offender," said Donna Coleman, president of the Children's Advocacy Alliance, a Nevada group.

It funded startup of the sex offender Web site and recently helped the Legislature tighten laws that govern offender registration.

Combining all four tiers, the state has 4,715 registered sex offenders. Of those, 42.9 percent were convicted of sex crimes that took place outside Nevada. Wideman would not speculate on the reasons for the high percentage of offenders who appear to have moved here after their crimes. (Some may have been living here but visiting elsewhere when they committed the sex crime.)

But Coleman, who lobbied the state to launch the site, attributes the high percentage to several factors. Nevada, and specifically Southern Nevada, are high-growth magnets that draw newcomers, both criminal and non. Her Internet research also suggests offenders themselves view Nevada as an "easy" state where enforcement of sex-offender registration is comparatively lax.

To use the Web site, the general public can search either by a specific offender name, car license plate number or ZIP code. A ZIP code search will yield a list of registered offenders who either live or work there. In most cases, however, the site gives only home ZIP codes because the offender did not have a job at the time he or she updated his or her file with local police.

Offenders are not listed by home address on the Nevada site, although the addresses must be added by July 2006, when a tougher state law takes effect. The city of Henderson, however, maintains its own Web site of sex offenders -- at www.cityofhenderson.com/police/php/sexoffender2.php -- and already provides more information about individuals than the state registry. Henderson's page gives the "100 block" for the street on which each of its Tier 3 offenders lives.

Ronald Hippie, for example, is listed as living in the 1500 block of Warm Springs Road. He received media coverage last year when he and his mother were spotted ripping down posters about Hippie that Henderson merchants had posted. Henderson police had mailed the fliers to the merchants, in keeping with the community notification process outlined in state law on sex offenders, Henderson Sgt. Dave McKenna said.

McKenna said the department is expanding its Web site to add precise addresses for Tier 3 offenders. It also is preparing an interactive database that will enable a site visitor to punch in a Henderson site -- such as a home address or school or park -- and generate a map showing the locations of Henderson offenders who live in a set radius around the designated spot.

Among Nevada's registered sex offenders, about 38 percent are noncompliant, Wideman said. That means 38 percent of offenders have failed to do the annual check that enables local enforcement to verify their latest whereabouts, and update the state's Web site.

By comparison, Florida and Arizona have noncompliance rates of about 5 percent, Coleman noted. Failure to comply is a Class B felony in Nevada, which could send an offender to prison.

Compliance enforcement is the responsibility of local police departments and sheriff's offices.

If they locate an offender who has failed to comply, they take their information to the district attorney. Coleman said stretched budgets keep police departments here from dedicating manpower to tracking down noncompliant offenders.

As well, she said she believes the Clark County district attorney's office does not follow up as aggressively on cases of noncompliance as it could.

The Clark County district attorney is "committed to enforcing the laws affecting sex offender registration," says Tom Carroll, a deputy district attorney who heads the special victims unit. "However, there are certain limitations as to how much we can accomplish."

He says it is "common" that a noncompliant offender who is arrested for something unrelated, such as a traffic offense, updates his or her information and becomes compliant "when they realize the threat of prosecution is imminent." Such offenders often get back in compliance before the paperwork from the police to the district attorney for prosecuting noncompliance is complete.

Wise use of limited resources means the district attorney's office does not prosecute the now-corrected violations, according to Carroll. But Coleman said such prosecutions would put all noncompliant offenders on notice.

"Zero tolerance (of noncompliance) costs money," Coleman said. "We can do Web sites and give people lots of time in prison, but until we really start funding" police and district attorneys to deter sex crimes by aggressive enforcement of registration law, criminals may continue to see Nevada as a comfortable place to live.

By July 2006, sex offenders in Nevada will have to adapt to other changes in state law. Offenders will then have to renew their driver's licenses annually.

That means the state every year will obtain the person's latest address and a new photo. Offenders who work in gaming jobs that require a work card also will have to update that document annually.

Failing to comply could cost an offender his or her job and transportation, as well as threaten a prison term.

Soon Nevada will participate in a new national registry of sex offenders. Nevada is among the first 20 states to join the registry, which is a pilot program of the U.S. Justice Department. The registry was set to launch Thursday, Justice Department spokeswoman Sheila Jerusalem, who is based in Washington, D.C., said in early July. The new site's Web address would not be released until shortly before the launch date, Jerusalem said.