Yaphank, NY -- The computer crimes unit of New York's Suffolk County Police Department sits in a gloomy government office canopied by water-stained ceiling tiles and stuffed with battered Dell desktops. A mix of file folders, notes, mug shots and printouts form a loose topsoil on the desks, which jostle shoulder-to-shoulder for space on the scuffed and dented floor.

I've been invited here to witness the end-game of a police investigation that grew from 1,000 lines of computer code I wrote and executed some five months earlier. The automated script searched MySpace's 1 million-plus profiles for registered sex offenders -- and soon found one that was back on the prowl for seriously underage boys.

That's something that MySpace has said it cannot do. Rather, it is seeking new laws that would make it easier to ban sex offenders from the site through an e-mail registry.

MySpace busts are rare in this unit. About half the work done by the eight detectives here is aimed at online predators, but the networking site poses challenges that open chat rooms -- a dying social scene among today's youth -- never did. "It's a dangerous place for kids," says Frank Giardina, a good-natured, 49-year-old detective with salt-and-pepper hair and a matching mustache. "It's also difficult for law enforcement."

That's because much of what happens on MySpace unfolds outside public view. The computer crime unit has erected bait profiles registered to fake underage teens, but so far the tactic has netted only one arrest. Proactively scouring MySpace pages is futile: The smarter sexual predators stick to private messages, and diligently prune their public comment boards of any posts from young friends that hint at what's happening behind the scenes.

Today's investigatory target, 39-year-old Andrew Lubrano, has been less careful, and now he faces his fourth arrest for a sex crime. Lubrano was sentenced to three years probation in 1987 for sexual abuse against a 7-year-old boy, according to police. In 1988, he got another probation term for second-degree sex abuse. In 1995, he earned a 3 to 9 year prison term for sexually abusing two boys he'd been babysitting, one 11, the other 9.

The parole board turned Lubrano down three times, and he was cut loose in September 2004 largely unsupervised, having served every day of his nine-year max. By November 2005 he was on MySpace, making friends.

In the beginning, Lubrano seemed to use the site innocently. But in April, he began adding teenagers to his friends list. One of the first was Jacob, a gay 14-year-old high school student in Virginia, who reports his age as 16 in his profile. Lubrano starts calling him "sex toy" and asking him about his living situation. Lubrano thanks another Virginia boy for adding him to his friends list by writing "Thanks for the a$$, I mean add."

Giardina has been posing as another 14-year-old boy in online chats with Lubrano, and he says he's received less nuanced communiqués from the offender discussing having oral sex with the fake teen. He shows me part of a chat log, Lubrano asking "u into hair? Like hary (sic) men? Where do you have hair at?"

Lately, Lubrano's been talking about meeting at a camp site or a movie theatre. Today the detective thinks his target is ready to firm up a tentative commitment to meet at a local bowling alley. A signed search warrant is burning a hole in Giardina's pocket.

Read the rest of this story at: Wired.com