Berkeley County investigator Kevin P. Murphy has spent the past few years sifting through the handiwork of child predators who abuse the young in myriad, twisted ways.

It's a tough and unsettling job, the revolting images and sounds difficult to shake off when the workday ends.

But for Murphy, a detective sergeant with the sheriff's office, the pay-off is huge when his cyber-sleuthing leads to the arrest of those who hoard and trade child pornography.

Each arrest represents one less person supporting the exploitation of children and a chance to maybe save some kid from sex trafficking or abuse.

"It brings me great satisfaction to use the skill set I have for that purpose," Murphy, an 11-year veteran of the sheriff's office, said. "When we catch these people, they end up doing hard time."

Murphy's endeavors earned him a trip to Washington, D.C., this week to receive a prestigious national award from the U.S. Justice Department.

Murphy received the U.S. Attorney General's Special Commendation award for his efforts to expand the South Carolina Internet Crimes Against Children task force's ability to investigate online crimes throughout the state and to train other agents and law enforcement agencies in computer investigations.

He was one of just seven people from four states honored for their efforts to recover missing children, rescue children from abuse and prosecute sexual predators. The ceremony took place during the agency's 31st annual commemoration of National Missing Children's Day.

"It takes very special people to perform such difficult - and in many cases heart-wrenching and life-changing - duties," Associate Attorney General Tony West said of the award recipients.

Murphy, who is assigned to the state task force, has been involved in several investigations targeting people trading and storing child pornography.

In fact, while Murphy and his wife were driving home from Washington, the state Attorney General's Office announced that a Summerville man had been arrested on child porn charges based on one of Murphy's investigations.

S.C. Attorney General Alan Wilson lauded Murphy for his aggressive efforts to find those who trade in child porn.

"I commend him for his relentless efforts to find those who victimize children, and to put them where they deserve to be - behind bars," Wilson said.

Murphy has undergone more than 139 hours of specialized training and works full-time at ferreting out and building cases against secretive pornographers who use online file-sharing programs to trade illicit images and videos. Since September 2012, he's worked on more than 100 cases that have netted about 24 arrests. But he's quick to point out that this is a team effort, with everyone from front line deputies to prosecutors helping him nab his quarry and put them away.

Berkeley Sheriff's Maj. Rick Ollic, who traveled to Washington with Sheriff Wayne DeWitt to attend the ceremony for Murphy, said the sergeant's work serves as a statewide model for how such task force investigations should be run. "His dedication is incredible," he said.

Reach Glenn Smith at 937-5556 or Twitter.com/glennsmith5.