The mystery hacker whose online infiltration has led to several arrests of suspected child predators -- including a California superior court judge -- was a 19-year-old loner who penetrated 3,000 computers around the world from his parents' basement in Langley, B.C.

In all of this, the Canadian hacker has remained anonymous, even in police affidavits -- until now.

Dubbed "Citizen Tipster" by police, Brad Willman, spent night after night writing a Trojan Horse program that gave him complete control over every computer that downloaded it.

Alone and in the dark, he sat for up to 16 hours a day monitoring hundreds of targets, secretly reading their e-mail and tracking their every step online.

He started keeping files on the targeted users. He tracked them for almost three years --recording everything. The majority of his targets were ordinary people -- but some in the files included priests, social workers, soldiers, police officers and justice officials.

He catalogued each file by degree of risk and focused on suspected child-porn producers and molesters.

This was his life. He had no friends in school and skipped the prom. Even these days, his only entertainment away from the computer is going to the odd movie, alone.

The son of a coffee shop owner, Mr. Willman, a.k.a. Omni-Potent, finds if hard to socialize and rarely answers the telephone. He can only be himself online -- staring at the screen and chewing sour candies.

Though never publicly credited, Omni-Potent is the same mystery hacker who led the Mounties to the capture and conviction of an Alberta man who offered his eight-year-old daughter up for sex through the Internet in 1999.

The hacker's investigations have exposed suspected child predators across Canada, the United States and Russia. Some of the suspects included foster parents, social workers and justice officials.

He has also helped find child victims.

He first set his fingertips on a keyboard at the age of five and taught himself to hack by the time he was 14.

He began targeting online child predators three years ago. He started turning in suspects two years ago, ignoring police threats that if he didn't stop he'd be arrested for breaching privacy.

He did all of this, for up to 16 hours a day, on his free time and in secret.

And it began as a game.

"I was just playing around with this program I wrote. I wanted to see how it worked. Then I got way more curious about what these people were doing. It's exciting to see something you build actually work. It means I have actually helped out. It challenges me and makes me work," said Mr. Willman, now 21.

The program, disguised as an image, allowed him to retrieve anything -- undetected -- once downloaded. He posted the image on several usenet groups used by pedophiles. In reality, the downloaded image was simply one retrieved from the user's own hard drive.

Some 3,000 users around the world downloaded the Trojan Horse program-- giving him full control of targeted computers.

"Then, I would stay up late at night to see what I could drag out of their computers, which turned out to be more than I expected. I could read all of their e-mails without them knowing. As far as they were concerned, they didn't know their e-mails had even been opened.

"I could see who they were chatting with and read what they were saying as they typed. I judged these people by reading their incoming and outgoing e-mails. I was more interested in actual abusers or producers. That was my priority --not the people that were just downloading images."

Sometimes the work was overwhelming, what with tracking every single e-mail for hundreds of people. "It did get quite busy. It was a lot of work to keep on top of it."

The motive behind his investigations was always to protect children "who can't protect themselves."

He often ignored police threats of arrest and instead pressed ahead, particularly in the case of Orange County Superior Court Judge Ronald Kline. After reading the judge's electronic diary, he concluded it showed an apparent plot to sexually exploit young boys at a private health club. "Sure, a violation of privacy you must cry, but if you have nothing hurting kids, the future of the world, then there's no reason to worry as that is all that Omni-Potent protects," he said.

In several interviews with the Ottawa Citizen, the hacker expressed frustration with police reluctance to pursue his information about child pornography producers. In some cases, he says police in Canada and the United States ignored his evidence packages.

In some cases, he says U.S. police and the RCMP have backed away from offers of reward for tracking down online child predators.

"Omni-Potent's service thus far has been provided without cost to the public. Not one dime has been provided to Omni-Potent and yet there has been tremendous success in providing accurate information.

"Technology is everyone's enemy whether they realize it or not. It is after all, technology which helped to find me and mess up important investigations by attempting to lift my veil," he said.

Mr. Willman says he measures his success by his "contribution" to protecting those who cannot protect themselves.

In the case against Judge Kline, U.S. detectives credit him alone for breaking the case. "The diary he retrieved gave us the probability that we needed to get the search warrant," said California Det. Ronald Carr.

The search warrant unearthed more than 100 images of young children engaged in sex acts.

In police affidavits obtained by the Citizen, the judge admitted that he authored the journal. The judge has not been charged with any crime for keeping the electronic diary, but has been charged with possession of more than 100 images of child pornography. Since that indictment, an alleged molestation victim has come forward and the judge now also faces sexual-assault charges dating back to 1976.

In the electronic journal, excerpted in police documents, the author writes exclusively about his sexual interest in young boys. The journal entries span May 2000 through March 2001 and detail the author's deviant sexual urges and the times and places where he meets young boys. These details, and his written thoughts about cases before him, made it easy for authorities to conclude the retrieved diary was genuine.

The judge, a Little League umpire, had contact with numerous boys at ball games, in a mall and at a private health club -- where he befriended vulnerable young boys with the hopes of exploiting them.

"You can't just charge in like you did with (a boy). How do I encourage him without pursuing him too hard? You have great entrÈ in the separation of his parents," says an entry dated June 6, 2000.

The next day, the author writes: "I gave a lot of thought today about this business of approaching these kids too fast ... He doesn't strike me as a lonely boy like (boy) was. You have to make them come to you or it just doesn't work," says a diary entry dated June 9, 2000.

After reviewing the journal, Det. Tracy Jacobson concludes in an affidavit that the author is a pedophile. "He refers to the child as 'gorgeous' and writes about how and when to approach the child, and plans his moves carefully. It is further my opinion these are the type of comments only a pedophile or a child molester would make," Det. Jacobson said.

In the journal, the author seems fixated with young boys and often writes about the problems of enticing them to be alone with him. He talks about buying them baseball tickets and giving them a tour around town in his Porsche Boxster. According to California Motor Vehicles records, a 2000 Boxster with the licence 4HTV361 is registered to Judge Kline.

Sometimes, he found it hard to control his urges. In one entry, the author writes about sitting next to a young boy at a pizzeria, and rubbing his back "with no resistance at all." Other times, the author wrote that when he was preparing to give a drive to a boy to a ball game, he likened it to getting ready for a date.

Because the author was noting the names of the boys and tracking their movement, Mr. Willman feared he would molest one of the targeted boys. In turn, the hacker forwarded the electronic diary to Predator-Hunter.com, an Internet organization created to stop child exploitation.

"Parents in a number of countries, I think, owe Omni-Potent a debt of gratitude for doing what he did. I don't endorse what he did as being legal, but law enforcement should seriously look at putting guys like him to work because they are obviously not getting the job done," said Wendell Krueth, president of the Predator-Hunter.com.

The Internet group conducted its own probe, then forwarded the files to the California Department of Justice. On May 8, 2001, Irving police Det. Ron Carr was assigned to assist the department in a probe into alleged child pornography.

He concluded the journal was genuine, then set out to track the hacker who built the case. Three months later, after tracing him to a Web site, Det. Carr travelled to Langley, just outside Vancouver, to interview Brad Willman, known only as "Citizen Tipster."

The hacker explained how the Trojan Horse program worked and then agreed to hand over his hard drives to police. They also wanted him to thumb through his files -- a tall order, he said, for one person.

"They wanted everything right away. I had to dig through all the information. And to go through my archives when it's just one person is pretty hard. They said they would see what they could do about compensating me for my time but I never heard from them again."

In the time it took to search his archives, he lost too many days to resume monitoring other targeted users. "When you're reading every single e-mail for hundreds of people it's impossible to keep doing it when you lose a week. You're too far behind."

The judge is now under house arrest in a two-storey home at the end of a cul-de-sac in Irvine, California. It will be the judge's defence that because the electronic diary, the cornerstone of the case, was stolen, the federal grand jury charges should be dropped.

The defence will also argue that the diary was stolen by a hacker who was working on behalf of law enforcement -- a charge Mr. Willman denies.

For now, Mr. Willman, at the behest of his parents, has stopped hacking.

"They liked what I was doing but they don't want me to do anything illegal."

Sometimes he regrets his online life. "My whole life has been online. I've literally spent half of my life on the Internet. I'm anti-social in real life. I've been on the computer too much to keep friends. I'm trying to get out more. And don't tell me about meeting girls -- boy oh boy."

He is now working hard to launch a computer security career and thinking about moving out of his parents' basement to assume a new identity so he can hack again.

"If I am ever to come back, it'll be on my own terms and no one will know ever again who I am."