Depending on the severity of their crimes, registered sex offenders in New Jersey must check in with authorities annually or every 90 days, and notify law enforcement when they change residences.

But 63 New Jersey men must think the rules don't apply to them.

That's how many sex offenders were listed as non-compliant on the publicly accessible New Jersey Sex Offender Internet Registry as of midnight Friday morning. The state's online database only includes sex offenders in tier 2 or 3 of New Jersey's three-tier system — those judged to be a moderate or severe risk of repeating their crimes.

In a best-case scenario, police learn they've lost track of an offender thanks to a tip from the public or during a routine address verification. But sometimes it's the offender's failure to check in that sends up a red flag.

"We do see it often," Sgt. Sandra Rodriguez of the Megan's Law Unit of the Ocean County Prosecutor's Office said. "Eventually, you're going to be found. It's just sometimes it takes a little longer than others."

The search for an offender starts close to home — interviewing family, friends and other folks in the community, trying to determine where the convicted criminal was last seen.

But officials in New Jersey have plenty of resources through the federal government as well. Rodriguez said if officials exhaust every possible tactic locally and still can't locate an offender, they turn to a special task force within the U.S. Marshals Service.

In some cases, an offender is unable to comply with registration requirements simply because he or she was arrested and thrown behind bars for another crime.

One offender from Ocean County was currently unaccounted for as of late this week. Bruce King from Plumsted Township was convicted of sexual assault in 2007. He's considered a Tier 2 offender, posing moderate risk to the public.

"By not registering, or by moving away and not keeping in touch with authorities, I think there is a huge danger to the community," former Union County Prosecutor Ted Romankow told New Jersey 101.5. "This isn't a situation where it's a minor crime that they committed. It's serious enough that they're on a registry."

The 63 non-compliant offenders are a small fraction of the 4,316 total offenders on New Jersey's official registry.

Non-compliance is, itself, a third-degree crime — and as such can include a prison sentence of between three and five years as well as fines.

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