BISMARCK, N.D. — A door in Steve Harstad’s office at the North Dakota Bureau of Criminal Investigation’s Bismarck headquarters looks like it leads to a closet. And it does, in fact, lead to a space only slightly larger than one. But in that little space, Harstad and others conduct investigations they hope will help keep children safer from online predators.

Harstad, a BCI special agent, coordinates North Dakota’s Internet Crimes Against Children task force, which includes the BCI and 45 other law enforcement agencies, prosecutors’ offices and federal entities. The U.S. Department of Justice’s Office of Juvenile Justice and Delinquency Prevention began funding task forces in 1998 to investigate online child victimization; now there is a task force in every state. Harstad estimates that North Dakota gets $200,000 annually for the task force.

Additional Photos Steve Harstad, who asked to be only partially photographed, says that education is key to stopping the online exploitation of minors. “We can’t arrest our way out of it,” the special agent says. Mike McCleary/The Bismarck Tribune via The Associated Press

The group investigates child pornography and cases of adults trying to lure minors by computer or other electronic means for sex. So far in 2012, officers involved in ICAC have investigated 40 such cases in North Dakota through July, Harstad said.

Bismarck police have made 10 arrests in those cases, police Sgt. Mark Buschena said. The officers have arrested six people this year for luring minors by computer and four for possessing child pornography. From 2008 to 2011, the department made two arrests for luring minors by computer and nine for child pornography.

The increase in cases of online child victimization in Bismarck is not necessarily evidence of an ever-growing number of adults trying to entice children or view child pornography. Instead, it’s a sign of the increased efforts by investigators in the Bismarck Police Department working with the ICAC task force.

Bismarck police Sgt. Gary Malo said two Bismarck police officers went through the training to work the ICAC cases but were then promoted and left the investigations section. Detective Scott Betz was appointed to the investigative position about a year ago.

Betz has investigated at least 10 cases of adults luring minors for sexual activity and two child pornography cases this year. Malo said other detectives have taken on additional cases, and Betz also takes on other assignments. Harstad said no North Dakota departments are able to have detectives dedicated only to ICAC cases.

“It could be a full-time job for two people here,” Malo said.

The child pornography cases mostly start in that closet-like office behind Harstad’s office. Harstad runs a program that gets information about the locations of computers using peer-to-peer sharing websites to share child pornography.

Once Harstad narrows down the probable location of the computer sharing child pornography, he enlists the help of other agencies involved in ICAC. Investigators get search warrants and use them to check homes where they have evidence suggesting they will find child pornography.

Previously, all devices within a home would have to be seized so BCI forensic investigators could scan them for obscene files. Now, some departments, including the Bismarck Police Department, have received equipment and training to run preliminary scans themselves, Malo said. Only devices shown by the scan to have the files on them are seized and taken to the closet behind Harstad’s office for a more in-depth look. If child pornography files are on the computers, prosecutors determine whether the case should be filed in state court or federal court.

Every picture and video found is sent to the National Center for Missing and Exploited Children so that investigators can try to identify the children. Some images and videos have circulated for years, and detectives recognize them. However, there always is the chance that a child being assaulted in a picture or video hasn’t been identified yet and is still being subjected to abuse.

“The first thing we want to make sure is, is it someone we can identify here and rescue?” Malo said.

The luring cases can start in a variety of ways. In some cases, parents or children report someone having inappropriate conversations with a minor online, and investigators take over, playing the part of the child. In other cases, investigators set up fake online profiles on social media sites, chat rooms and other sites and pose as children.

Where the file-sharing cases can progress in several days, the luring cases often can take months.

In those cases, officers — often middle-aged men — have to “become” teenage girls. Harstad said that means keeping up on pop culture and trends that interest teens. The officers have to know abbreviations and slang and styles of talking, texting and writing common to teenagers. They have to be available to communicate at times when teenagers would be available, but they aren’t allowed to take their work home with them.

“Once you start, it’s hard to do a good job by starting and stopping,” Mandan police Sgt. Jay Gruebele said.

“Quite honestly, the guys who have kids are probably better at it,” Harstad said. “I think it’s a challenge, and some guys have it and some guys don’t.”

Gruebele said officers have to research and be alert to make sure they don’t say something a 13-year-old girl wouldn’t say. All the investigators in Mandan are involved in ICAC but have had limited time to work the cases. Now, Gruebele said, the investigations division is fully staffed again and hopes to do more such work.

“We’re going to definitely hit that a little harder,” he said.

Harstad said he’s continually surprised at how many cases arise, considering the publicity surrounding luring cases.

“You’d always get asked, ‘Are you Chris Hansen?’ ” Harstad said, alluding to the host of NBC’s “To Catch a Predator” series that ran from 2004 to 2007.

Malo said the number of cases hasn’t surprised him.

“I’ve known it for years, but we couldn’t work them,” Malo said. “I knew it’s been out there ever since the Internet.”

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