The following story was published by Marinus Analytics, a spinoff of Carnegie Mellon University's Robotics Institute that uses artificial intelligence, machine learning, predictive modeling and geospatial analysis to combat sex trafficking. (Reprinted with permission from Marinus Analytics. Names have been changed to protect identities.)

The Outcry

It started with an outcry from Allie, who was pimped two years ago by a violent trafficker who went by the name Julian. She told Detective John Patterson, "I want to get out of this because of what Julian's done to me. And he did it to a 15-year-old girl, too." Similar cases of this scope — which grew to 21 identified victims — would usually take a year. Detective Patterson built this case in about three months. He credits the importance of good experience, training and technology tools like Traffic Jam.

The Violent Pimp

Julian was a violent pimp who required a $1,500-per-day quota for each victim and would beat any violators. He had been arrested many times in the past —for running his victims over with a car, for strangling one of his victims until she passed out, for punching and assaulting others. He also threatened to kill his victim's children if they didn't work for him.

Julian recruited his victims in person and on social media apps. He broke one victim down by recruiting her to work as a stripper, and then repeatedly raping her. When she still refused to sell sex for him, he withheld food until she agreed. When she tried to escape, he used a location-tracking app on her phone to chase her down. He found her, assaulted her and put her back to work.

Traffic Jam

Detective Patterson used Allie's testimony to begin piecing together the case. By searching victim's Facebook photos through Traffic Jam's FaceSearch, he found their ads posted across the country. "I used Traffic Jam to map out the course that Allie exactly described," he said.

He was searching for Jessica, an underage victim Allie had told him about. He scrolled through Jessica's Instagram, and found the most recent pictures she posted of herself, which were more than two years old — from when she was 15. "I didn't think it would lead to anything, because it was such an old photo," he said. "But I thought I'd run it through FaceSearch just in case. I couldn't believe it when the two-year-old photo returned top matches in FaceSearch that looked just like her." The Traffic Jam trail showed that she was posting from California, but had recently posted in his city.

Allie told him about another victim, Sammy. He found some year-old pictures of Sammy on her Facebook profile and uploaded them into FaceSearch, which returned top matches that looked nothing like Sammy. "I thought the matches weren't her, they just didn't look like her," Patterson said. He sanity-checked the top matches by checking the timing and location of the ads. Then, he said, "I found that one of the phone numbers in the ad was registered to her name. That made me realize that the pictures from the FaceSearch results were a correct match, but I didn't recognize her at first because she had changed her appearance so drastically." When the appearance of the victim looked completely different, FaceSearch still made a positive match in seconds.

Where Are They Now

By using technology tools like Traffic Jam in conjunction with victim interviews and evidence gathered through search warrants, Detective Patterson assembled a history of money transfers from the victims to their pimp. He confirmed that many of Julian's victims were working in different states and wiring their earnings back to Julian. He determined Julian was making about $15,000 a month from two girls alone, and he had a total of 21 victims during the span of the investigation.

The police department received an arrest warrant for Julian for six felonies. Today, this violent trafficker is in jail without bail, awaiting prosecution and potential life in prison for his crimes, all thanks to the tireless efforts of Detective Patterson and his team.