For the state's leading investigator of child porn, building a molestation case against Ville Platte surgeon Dr. Charles LaHaye was easy. The evidence was on digital tapes, CDs, computer disks and hard drives.

But as a law-abiding citizen, it was not easy for James Piker, chief investigator and prosecutor for the state Attorney General's high-tech computer crime unit, to look at LaHaye's victims begging for mercy.

"It was frustrating and psychologically taxing investigating the LaHaye case," Piker recently said at his office in Baton Rouge.

Piker has become known as "the porn guy" by his colleagues because on every computer he looks at, he digs up people's dirty little secrets.

He and his staff of cyber detectives have taken a lead role in Louisiana in fighting Internet crimes like child porn, hacker attacks, fraud and identity theft.

Piker's team of five cybersleuths capture and analyze computer data for local and state law enforcement agencies.

Since it was started in January 2000, the high-tech unit has helped prosecute 22 people for computer-related crimes - the most infamous being that of LaHaye, who received a 56-year prison sentence in October after pleading guilty to 16 separate sex-related charges involving 12 victims. The 39-year-old surgeon admitted videotaping himself molesting young boys who appeared to be drugged and begged him to stop.

Piker used powerful computers in the state's forensic laboratory to recover digital video images of LaHaye molesting the boys. One of LaHaye's computers had so much pornography on it, the hard drive couldn't be cleaned of the child pornography, he said.

"(It) had to be taken apart," said Piker as he stood in the midst of computer towers, flat screens and paper bags filled with computer equipment forfeited by LaHaye as part of his plea agreement.

Recently, Piker began comparing the sketch of a serial killer linked to the deaths of four Louisiana women with Internet personal ad photos of men found on the computer of a woman killed in West Baton Rouge Parish. Piker would not identify the victim.

But the state Attorney General's Office was asked to investigate the homicide of Geralyn DeSoto, 21, at the request of her family.

DeSoto was beaten and stabbed to death. Her neck was slashed. Two of four other women linked to the serial killer by DNA evidence were killed by the same method. However, DNA evidence from the serial killer has not been linked to the DeSoto homicide.

About 80 percent of the high-tech unit's caseload is child pornography. The other 20 percent is filled with tracking down Internet scams and fraud.

Inside the unit's forensics laboratory room, investigators such as Scott Turner look at computer hard drives to trace a suspect's computer activity. The hard drive is the computer's storage cabinet. Every key punched, Internet Web site visited, transaction and message is filed away - even deleted items. Deleting items doesn't punch information out of the hard drive, it only changes the characters and moves them around, Piker said. In a program investigators use to search hard drives for keywords, the deleted items show up in red.

No matter what type of case, investigators check for child pornography, Piker said. When they find it, heartsick frustration usually follows, Piker said.

Piker said most people have the misconception that the majority of child pornography on the market depicts 15- or 16-year-olds and that it's hard to tell if they are minors. However, the average age of children used by pornographers is 6 or 7, he said.

The unit recently applied for a $300,000 grant that would allow for a full-time Internet Crimes Against Children Task Force that would staff undercover agents on the Internet every night.

Computer fraud and identity theft, including making bogus checks, are also problems.

Piker and members of his unit learned firsthand that no one is immune to Internet crime. After one of the investigators went online to check for flights to a conference in Atlantic City, they later discovered that someone had used his credit card to charge $5,000 worth of airline tickets.

"It happens to everybody," Piker said.

UL-Lafayette professor Istvan Berkeley remembers first using the Internet in graduate school in 1989 to e-mail messages to one of his professors in New York. But with the instant access and communication between people, the Internet has evolved into a playhouse for scams, identity theft, child pornography trafficking and psychopathic plots.

"It's the perfect realm for a predator," Berkeley said. "They could be anonymous in the system. It could be difficult to track someone down, but also possible, unless they're technically sophisticated."

Recently, the Lafayette Parish Sheriff's Office searched a computer used by Trineisha Dene Colomb to find leads to her homicide, which was later linked to the serial killer. Early in the investigation, the family of Colomb, who was found dead on Nov. 24 in a wooded field in Scott, told investigators they feared she planned meet someone she knew from the Internet.

Because of the family's prodding, detectives checked out Colomb's use of the Internet, said Lt. Craig Stansbury, sheriff's spokesman.

"It's a different way to follow up on a lead," he said.

But there was difficulty in surveying the computer because Colomb didn't own her own computer and accessed the Internet at the public library, where hundreds of users log on daily.

Computers give insight into a victim's or potential suspect's life that even close family members or friends may not know about, Piker said.

"In a homicide, a lot of time what we can do is give investigators a glimpse into the person's alter ego, to things that no one in the brick-and-mortar world would know about," he said.

"If you could show me a place more intimate, I would be surprised," Piker said.