Three months ago, State Trooper Jonathan Otto, 33, of the Arizona Department of Public Safety pulled over a car that had caught his attention by traveling 104 miles per hour long after midnight, just south of Kingman. He smelled marijuana in the car. It was driven by a man with an adult female wearing only lingerie. Their passenger was a female juvenile whose fake document showed her to be 18. She was, Otto says, “not wearing a whole lot of clothing.”

The adults had taken this 16-year-old from California to Arizona and were heading for Las Vegas. The girl gave Otto the California phone number of her grandmother, who immediately told him the girl might have been in prostitution since she was 15. Trained in interview techniques for such situations, and experienced at noticing people who somehow do not belong together, Otto correctly suspected DMST — domestic minor sex trafficking.

Trooper Mitch Jergenson, 46, stopped a car driven by a man whose passenger was a 17-year-old girl he had gotten to know via Facebook and other social media. He had paid for her ticket from California to Phoenix and was taking her to Las Vegas. She said she was going to be a “model,” then said she was going to work in a strip club. This, says Jergenson, is “the start of a process” whereby minors often wind up working the streets. “Las Vegas has strict regulations, but … .”

Sgt. Scott Reutter, 47, who watches the motels near the Phoenix intersection of I-17 and I-10, where prostitutes are active, approached a young girl talking to an older man. She said she was 22. Reutter, whose daughters are 22 and 19, thought she was “14, maybe 15.” She had been a runaway for 17 months, since she was 13, and said that if she were returned to the custody of child services she would run again. After a 10-minute hearing, she was returned. She immediately ran, and did so repeatedly. To be in law enforcement is often to feel condemned to bailing an ocean with a thimble.

Frank Milstead, too, knows how Sisyphus felt. When nature designed him, it had a director of the Department of Public Safety in mind. Large and laconic, he is the 54-year-old son of a Phoenix cop and, although he spent some time doing stand-up comedy, he knows in the marrow of his bones that “there are so many people out there who want to take advantage of other people.”

It is unclear how many victims of DMST there are because for many reasons the crime is not often reported by its victims. They are, Milstead says, usually abducted, sort of, from “some environment where nobody missed them,” adding, however, that traffickers cannot control “people who are unwilling.”

But many trafficked minors, “who no one had made to feel valuable,” are, Milstead says, “chronic runaways” with attenuated capacities for self-determination. They are products of poor or nonexistent parenting; their traffickers provide food, shelter, a simulacrum of caring, and drugs that produce dependency. Milstead guesses that 80 percent are addicted. Hence, they engage in “survival sex.”

Milstead’s troopers patrol motel parking lots and get to know those who do the motels’ housekeeping and notice suspicious activity. Big sporting events, of which Phoenix has many — the Super Bowl, the Final Four, NCAA championship football games — attract traffickers. Troopers also watch bars and nightclubs where minors are offered for sex, and, increasingly, monitor the internet and social media.

The website Backpage, whose founders live in Arizona, began as a place for normal classified advertising but, a U.S. Senate investigation concluded, found its most lucrative business being a sexual marketplace. The New York Times reports that law enforcement officials say Backpage’s “dating section” often “used teasers like ‘Amber alert’ and ‘Lolita’ to signal that children were for sale.” According to the Times, “In the midst of a Senate investigation, a federal grand jury inquiry in Arizona, two federal lawsuits and criminal charges in California accusing Backpage’s operators of pimping children, the website abruptly bowed to pressure in January and replaced its sex ads with the word ‘Censored’ in red.”

Holding up his smartphone, Milstead, whose vocation reinforces his inclination to look on the dark side, says: “Leaving your kid alone at night in his room with this? You might as well leave him or her in the city park downtown. Anything is available on a phone.”

© 2017, Washington Post Writers Group