“It’s strategic and has a purpose in developing girls as a product for sale. It degrades the girls’ sense of themselves and creates an objectification where girls devalue themselves.” Although many court documents didn’t necessarily track violence in such cases, researchers still found evidence of pimps using severe violence and threats against 34 percent of victims.

• Vulnerable juveniles were targeted, sometimes by peers, in places such as schools, parks, malls, bus stops, parties, treatment facilities and juvenile detention centers.

• Traffickers often targeted runaways, homeless kids, teens living in poverty, youth with cognitive delays or chemical use or history of abuse.

• Traffickers typically faked romantic interest in a juvenile, then used sexual, physical, psychological and verbal violence to prevent the juvenile from resisting.

Bobbi Larson, a victim of sex trafficking, examines items in an evidence bag at the Minneapolis Police Department.

It was filled with clothes, mostly negligees, that she had worn while she was trafficked.

A 20-year-old man assaulted and tried to drown a Minneapolis teen to force her to make money selling sex.A runaway girl was threatened with a gun and forced to turn tricks in a north Minneapolis house.A pimp threatened to kill a teen’s baby if she didn’t continue to work for him.The degree to which traffickers use violence as part of a structured business strategy surprised researchers who on Wednesday are releasing a preliminary study of the business strategy behind the juvenile sex trade in Minneapolis.Funded by the Women’s Foundation of Minnesota and the University of Minnesota Children, Youth & Family Consortium, researchers examined nearly six years of Minneapolis police and Hennepin County district court records, looked at seven years of media reports and interviewed 89 people who work directly with victims.“I was surprised by how organized and strategic the use of violence in these trafficking operations really is,” said Lauren Martin, director of research at the university’s Urban Research Outreach/Engagement Center, one of the study’s authors.