Yet another example of how the people we trust to "save" women and girls from prostitution are often the ones they need protecting from: a District of Columbia cop has been arrested for armed robbery, assault, prostitution, and several sexual offenses after paying a 15-year-old girl for sex and then stealing the money back at gunpoint afterward. The officer, Chukwuemeka Ekwonna, had been with the D.C. Metropolitan Police for a little over a year.

In January, Ekwonna, 27, met the girl on the app Tagged and she agreed to meet him for sex in exchange for $80, according to police. After paying her and then having sex in his car, Ekwonna allegedly threatened her with a gun and demanded she give his money back, which she did and fled. The D.C. police Internal Affairs Division and cops from Anne Arundel County (where the meetup took place) are investigating, and Ekwonna has been suspended.

In March, the Department of Homeland Security—increasingly a participant in minor prostitution stings across the country—came across the 15-year-old girl and had "concerns about possible human trafficking," according to NBC Baltimore. "However, police said the victim was acting on her own," the station reports.

Indeed, Anne Arundel County police state that their "investigation revealed the juvenile female was acting on her own and was not a victim of human trafficking, however she is not a target of any criminal investigation related to this case."

But legally, it doesn't matter—at least not when we're dealing with perpetrators who aren't cops' colleagues. Under federal law, anyone engaging in prostitution before their 18th birthday is defined as a child sex trafficking victim, even when "acting on [their] own." And anyone who solicits someone under 18 for paid sex is committing the federal crime of sex trafficking of children, regardless of whether they know the minor's real age. Meanwhile, Maryland also defines sex-trafficking as any inducing into or assisting a minor in an act of prostitution, no force/fraud/coercion required.

DHS doesn't even shy away from charging teenagers working with other teenagers as child sex traffickers if one of them is above age 18, so why are we seeing the agency leave this case—where the the conduct in question is so much more severe—to local police? Don't get me wrong—I think Homeland Security's general involvement in prostitution and domestic sex trafficking cases is a bad idea to begin with. But if the agency is going to do so, it would be nice to see it go after authorities who egregiously abuse their power with the same zeal it does young Ghanese refugees, Asian massage-parlor staff, and gay escort sites.

DHS has also been big on training hotel staff across the country on how to spot the "signs of sex trafficking," by which it really just means signs of possible prostitution (check out some of their tips here). This week, the ploy paid off by snaring a Secret Service agent on Vice-President Mike Pence's detail. The off-duty agent was caught leaving a tryst with a sex worker in a Maryland hotel room after the hotel's manager reported "suspicious activity" in the room to local police. The Secret Service agent was arrested and charged with solicitation.

Ekwonna was arrested this week on two counts of sexual offenses in the third degree (a category which includes adults having sex with teenagers), several handgun-related offenses, and one count each of robbery, armed robbery, first-degree assault, second-degree assault, reckless endagerment, and prostitution. His victim was able to identify him from photographs, police said.