Some of Casper's most disturbing criminal cases come to light in a small room not far from the Hall of Justice.

With its unadorned, beige walls, the room is not much to look at. There are two chairs, one purple, one multicolored, separated by an easel with white paper. A box of tissues sits on the floor, which is covered by an olive rug.

A tiny camera in the wall, and a microphone in the ceiling, hint at the true nature of this place. It's here, in the interview room at the Children's Advocacy Project, where investigations into the sexual and physical abuse of children begin to take shape.

Physical evidence is a rarity in these cases. They are instead built around the stories of the children who are brought here. Some haven't even reached kindergarten. Others are not far from adulthood.

The children speak of acts that make most adults cringe and want to turn away.

The crimes can take a toll on the men and woman tasked with solving them. It's overwhelms some and makes others numb. But it can also be the most rewarding work they will do.

"It was one of the few crimes I felt I could make a difference," said Kathryn Davison, who investigated sex crimes for almost six years for the Casper Police Department. "I guess I just felt that was what I needed to be doing."

Working these cases means working with physically and emotionally devastated victims and families. It means peering into the worst kind of crimes against victims too young to defend themselves.

"You can replace a stolen stereo, but it is impossible to replace a child's stolen innocence," Davison said.

In Natrona County, the investigations are not solely the purview of police and prosecutors. The Department of Family Services, and medical and mental health professionals, also have roles in the process.

At the center is the Children's Advocacy Project, a nonprofit organization that acts as a hub around which the various agencies do their jobs. It's where they come together to discuss cases and monitor interviews with child victims.

The CAP building has two interview rooms, along with a medical office painted with an ocean scene, complete with a giant sea turtle swimming on the ceiling. Down the hall are a pair of monitoring rooms, one filled with boxes of blue CAP sweatshirts, the other with a map of sex offenders hanging from the wall.

Since child sexual abuse cases generally don't offer much physical evidence, forensic interviews of the victims become critical for a successful prosecution.

"It's basically just fact finding," said therapist Nicole Rosenberger, who conducts forensic interviews at the CAP center. "You're just trying to get the facts. You are not judging, you are not helping, you are just there to figure out what happened, if anything did happen."

Details are essential. Detectives can use specific information about, say, a bedroom, to validate a child's story, explained Casper police detective Tim Doll.

"A lot of times, we don't have the physical evidence due to the time before the children are able to repeat (their stories)," he said. "We do what we can to confirm the story. We try to confirm what the child saw in the room, what was on the computer."

Victim statements alone might not be enough to convince a jury to convict a defendant, said Assistant District Attorney Michael Schafer, who's been prosecuting sex crimes in Natrona County since 1993. That means investigators must do everything they can to corroborate a victim's story.

"You really have to go into a great amount of detail if you are going to succeed in these cases," he said.

Most of the time, the perpetrators are known to the child. Dolls said he's only had two cases this year, out of about 35, that involved strangers.

Although the interviews are taped, if a case goes to trial, the victim usually has to take the stand, Schafer said. It's a difficult process, and one which Schafer doesn't know exactly what will happen.

To prepare, the veteran prosecutor usually meets with the child victims multiple times.

"I spend time just getting to know them," he said. "I don't even talk to them about what happened the first time or two.

"We get to know them, we decide, number one, are they able to do it? Will it have a traumatic impact? If we feel satisfied they can, we will call them to the witness stand."

Taped forensic interviews, however, can often prevent a case from ever going to trial. The defense sees for itself how well a child communicates his or her story and opts for a plea agreement.

The work can take an emotional toll - on victims and authorities. Even when a case goes right and a defendant is convicted, the victory can be hollow.

"I've had many cases where you've had a trial, succeeded with a conviction, yet there was still so much impact on the family, that it was anti-climactic," Schafer said.

Several years ago, Schafer said he seriously considered getting out of sex crime cases. Although he ultimately decided to keep on, it's not surprising that he contemplated doing something else. Prosecutors and police who handle such cases experience higher burnout rates, he said.

"I take it one day at a time, one week at a time, one case at a time," he said.

Child cases may be more rewarding to investigate than other type of crimes. But they can also be more difficult when things don't work out as hoped.

"Sometimes you can't get enough to move forward with a case," Doll said. "Those are the ones that stress on you."

Ironically, the brutal nature of the crimes also help keep investigators focused and motivated.

"Sure, there are times you get bombarded with so many you wonder if this is ever going to end," Davidson said. "You think, 'Are we doing any good?'"

"It was very easy for me to keep focused because I wanted the child to be safe and have them in a better environment," she said. "So I'd always keep focused on what I needed to do to get my job done right."

The work is not for everyone. Davison said she's known of officers who can't cope with the work. Even Amanda Moeller, who runs the CAP center, had some misgivings before she took the position.

"I turned down the job at first," said Moeller, who went through the entire interview process before saying no thanks. Then she changed her mind.

"Somebody needs to do this and it should be me," she explained.

"It's very satisfying at the end of the day, when you know you made a difference in somebody else's life," she said. "It is rewarding when we find out someone is being punished at some level. There's not really many days, really none, that I don't want to come to work."

Reach Joshua Wolfson at (307) 266-0582 or at josh.wolfson@trib.com.