MICHAEL MULVEY/DMN

"I think it's a huge mistake when law enforcement partners with citizens to do investigations," says Brad Russ, director of training for the Internet Crimes against Children Task Force program.

For a while this summer, it seemed that the usually quiet town of Murphy was overrun with men trying to meet underage girls for sex. In separate incidents, police arrested four men on charges of online solicitation – all within about a week.

None of the men actually lived in Murphy. And it was hard to imagine that this small Collin County town had suddenly spawned an epidemic of cyber-pedophilia. So why were so many alleged child predators interested in traveling there?

Perverted Justice.

This summer, the Murphy police became one of about a dozen Texas law enforcement agencies working with Perverted-Justice.com, an Internet watchdog that received nationwide attention after helping NBC's Dateline run stings on dozens of men caught trolling chat rooms to meet children for sex.

Some say the volunteer organization is a selfless grass-roots movement that helps stop potential molesters before they can hurt children. Others call it a vigilante outfit that uses harassing tactics that tromp on privacy rights – including by posting online the names and addresses of innocent family members who are related to potential pedophiles.

In Murphy, Perverted Justice has helped police jail a retired eye doctor from Tyler, a business traveler from Missouri, a former sailor who says he is addicted to sex and a Plano office worker. All the court cases are pending.

"Every one of these men came here, or planned to, thinking they were going to meet with a 13- or 14-year-old child," said Murphy Police Chief Billy Myrick. "So even if these guys don't live in Murphy, this shows their willingness to come here, or near here, and that's a great concern for us."

Xavier Von Erck, who founded the Oregon-based site three years ago, says that his organization has been integral in more than 200 arrests and at least 76 convictions of child predators, and has exposed the deviant behavior of more than 1,000 men all over the U.S.

"We've had a conviction every week of the year so far," Mr. Von Erck said. "We don't expect that number to go down."

He added: "I want pedophiles to go to a Web site and see a 12-year-old girl or a 15-year-old boy and think to himself, 'Oh, I better not talk to them because I could get arrested and show up on a nationally viewed Web site.' I want us to work as a deterrent."

But some law enforcement experts worry that the group's aggressive actions and questionable evidence-gathering methods result in some people being treated as if they are guilty without being convicted of a crime.

"I'm a strong proponent of citizen involvement with law enforcement," said Brad Russ, director of training for the Internet Crimes Against Children Task Force program, which is funded by the U.S. Department of Justice to train police across the nation to combat computer crimes.

But he added: "I think it's a huge mistake when law enforcement partners with citizens to do investigations. ... I'm very concerned about entrapment issues."

At least 21 men in Texas have fallen into Perverted Justice's trap, and so far, three have been convicted, the group says. In Murphy, Perverted Justice has accounted for about one-third of the city's 13 felony arrests so far this year. "That's a big deal for a city and a department of this size," Chief Myrick said.

Perverted Justice's roughly 60 volunteers who pose as children range in age from college freshman to retirees. They enter Internet chat rooms and wait.

Within minutes, men begin sending them private messages. They sometimes send pictures of themselves nude or masturbating. If a man solicits sex, the volunteer finagles his phone number and address. In phone calls, volunteers with young-sounding voices seal the deal.

In one of Murphy's cases, a man traveled from Tyler to the Dallas area for a rendezvous.

"The work they do is unbelievable," said Murphy police Officer Kevin Carter, who encouraged his chief to work with Perverted Justice after seeing the group's results on Dateline's popular "To Catch a Predator" series.

The show – a new set of reports airs this week – features a parade of men lured to houses around the country where they believe they are meeting children for sex. Instead, they are confronted by Dateline cameras. On one show, a man showed up nude to meet his prey.

Lt. Chad Bianco of the Riverside County Sheriff's Department in California said child predator investigations can take months of an investigators' time – which resource-strapped, small- to mid-sized law enforcement agencies don't have.

Perverted Justice "is a tool that costs nothing but gets the same outcome," said Lt. Bianco. His office has arrested more than 50 people in front of Dateline's cameras. "Law enforcement agencies that don't use this are dropping the ball."

When Perverted Justice started work in 2003, getting police to take the tips seriously was difficult. Nowadays, the group says that it works almost exclusively with law enforcement, posting chat transcripts only after police have secured the evidence they need to make a case.

But before it started working with police – and even now when police ignore tips or are slow to respond – the group seems to relish taking matters into its own hands.

After exposing a "wannabe pedophile," the group sometimes deploys a small online army to phone the men's wives, girlfriends and employers, and threatens to paper their neighborhoods with fliers labeling them pedophiles. Sometimes it posts the degrading pictures the men have sent to the "child" during online chats.

Only when the men apologize does Perverted Justice consider taking down their personal information. They also must prove to the group that they are in counseling by waiving their privacy rights and allowing Perverted Justice to contact their therapists, Mr. Von Erck said.

In February, Fort Worth school percussion instructor Anthony Horton, 28, was caught talking dirty to a volunteer pretending to be 13. After news of the bust was posted online, calls poured in from "all over the United States," he later told Fort Worth school officials.

According to school documents, Perverted Justice told him that unless he sought help and could prove it, they would begin printing fliers labeling him a pedophile.

Mr. Horton, who used the screen names "arlingtonhungman" and "johnholmes817," wrote an apology to the group, known by Perverted Justice as a "right of reply" and available to all men busted by the site.

Mr. Horton could not be reached for comment, but in his apology message, which is still online, he wrote: "I would never ever even think about sleeping with an underage girl. ... I am truly sorry, and will never in my life, go into another chat room."

Within hours of quitting his teaching job on Feb. 28, Irving police arrested him after they say he tried to solicit one of their officers posing as a 14-year-old. The case is pending in state court.

Mr. Von Erck said his group's tactics are far from harsh, given the nature of the men it's exposing. "I don't regret anything that we've done. ... We're posting truthful information, and we're alerting the public to it. In a way, it's analogous to the sex offender registry."

But sex offender registries don't "list the names and background information of neighbors, employers and family members of the accused," said Scott Morrow, founder of Corrupted-Justice .com, a Web site he launched to warn the public about Mr. Von Erck's tactics.

Perverted Justice members share information about their targets in internal forums, encouraging "contact" with them and their families.

Mr. Morrow said that amounts to harassment "designed to destroy a person's life."

Some computer crimes experts say the group has good intentions but is endangering people's rights and could derail cases by leading a perpetrator into talk about sex and otherwise interfering with legitimate police investigations.

For example, a Massachusetts athletic director was "busted" by Perverted Justice but avoided prosecution in 2004 after authorities couldn't find his computer hard drive.

Mr. Von Erck said the case was an anomaly. He points out that an assistant principal in Rhode Island was convicted after his encounter with Perverted Justice – even though his hard drive also disappeared.

The FBI won't say whether it would recommend that law enforcement agencies work with Perverted Justice, although the bureau has successfully pursued men busted by the group.

"We welcome any tips that help us solve a crime," said Paul Bresson, an FBI spokesman in Washington. But he added, "we don't encourage the public to take action. ... There are potential risks trying to take matters into your own hands."

In Texas, Perverted Justice says, it has written agreements with 14 police agencies – which Mr. Von Erck declined to name – promising that if volunteers identify a potential predator, they'll contact the authorities.

Numerous cases are working their way through the courts, and at least three men have been convicted in cases out of Lubbock, Killeen and a San Antonio federal court.

But many of Texas' largest police departments – most with their own cyber-crimes unit – say they probably wouldn't partner with Perverted Justice.

Lt. Ches Williams, the head of Dallas' Crimes Against Children Unit, widely recognized as a national leader in cyber-investigation tactics, said he would accept tips from the group, but that's about it.

"We just can't take that evidence and go straight to court, unless we can verify it's accurate," he said. "We might build on what is given to us, but we have to be completely satisfied that we are meeting all the legal requirements."

Police officials in San Antonio and Austin said they had no plans to work with Perverted Justice.

Fort Worth police would "reluctantly" work with such a group, said Lt. K. Rodricks, who heads that department's special investigations section. "We don't want to get in the business of adding to Internet vigilantism."

Mr. Von Erck said his group has long had to weather criticism from some out-of-touch pockets of law enforcement. The former tech support worker, who legally changed his name several years ago, spends all his time running Perverted Justice, relying on meager T-shirt sales and a controversial one-time $100,000 consulting fee paid by Dateline.

"It's the old boys attitude," he said. "They say, 'They're citizens, they can't be as good as us.' It's almost kind of an elitist thing. It doesn't really bother us, because, frankly, we faced a lot of that back in the day before we established our credibility. Now, police are coming around.

"It's an extreme minority that wouldn't work with us."

In Murphy, Chief Myrick is glad his department made the call to Perverted Justice.

"We felt like this was an important enough category of crime that we wanted to jump in there," he said. "We want to keep these people from even having the opportunity to come to our city."

E-mail jtrahan@dallasnews.com and ccolgin@dallasnews.com

The number of children ages 10 to 17 who use the Internet

Children who have been sexually solicited online

Children aggressively solicited after online contact (through meeting requests, phone conversations, gifts, etc.)

Children asked to run away from home by a solicitor

Online sex solicitations reported to authorities

Children who told their parents about online solicitations

Number of children out of 1,500 surveyed who said they were sexually assaulted by someone who solicited them online. (Both were girls, and authorities were told in both cases.)

SOURCES: A study funded by the National Center for Missing & Exploited Children. For the study, 1,500 children between 10 and 17 were interviewed in 2005, and U.S. Census Bureau population statistics were used to extrapolate the number of total children thought to be Internet users.