The underground sex economy in Dallas, you probably won't be surprised to know, is thriving. Not thriving quite like the local trade in drugs ($191 million per year) or guns ($171 million), but it's substantial, pulling in an estimated $98.9 million per year.

That's at least the figure reached in a Justice Department-sponsored study -- The New York Times calls it a "landmark" -- released today by the Urban Institute, which examined prostitution and sex trafficking in eight American cities.

The report is probably most compelling for the granular look it gives at each city's sex trade, based on statistical analysis and interviews with cops, pimps and prostitutes.

In Dallas, the cheapest sex work is found in poor, drug-infested neighborhoods, where crack or meth addicts sell themselves for as little as $5 or $10. One step up the chain are the street-level pimps, who gross an average of $12,000 per week from girls working street corners and the Internet. These comprise the majority of Dallas' sex market.

The profile of your average pimp has shifted slightly over the past couple of decades, the report says. In the '90s, they were easily identifiable by their clothes and cars and often held "pimp parties." That's no longer the case, though they are still typically black men, 25 to 30 years old, who often learned their trade from a father or uncle.

They generally have a handful of girls, upon whom they impose a strict daily quota. According to one Dallas cop the researchers interviewed:

$1,000 a day [quota]--doesn't matter how you got it--as long as you got it. So these girls were stealing, and that's where prostitution encompasses all aspects of crime because a girl's got to make a grand, it doesn't matter how she does it. So they take watches, so two or three girls, two of 'em are robbing him and the other ones are going through the [truck] and taking all the stuff out of there--they get an ATM card. You've got the robberies, you've got the burglaries, you've got the personal thefts, all these part one offenses surrounding this one issue.

Some pimps stick with adults as a way to minimize their chances of being busted. Others are less scrupulous about age. According to another law enforcement official:

For some, they need the grooming process, I think that our society changes ... but if you get a runaway from the West End, you give her a place to stay, you give her some food, you [get her to turn in] two days. ...

One of the other things is the Myspace, and MocoSpace. Believe it or not, people still use them, and the ones that are using them are usually younger, and pimps are on there like crazy. We just had one two weeks ago, that we got a call from [police department] and when we interviewed the girl, she took the laptop and opened it up, showed us, and there she was taking self-pictures of her in her thong and a little top on and I'm like, "Ok, and who put these on?" She says, "Oh I did." She goes, "Yeah, this is a hook-up site." That's what she was using as a hook-up site. So that's another way that they're getting them. They'll befriend them, it's glorified now to be a pimp, you look at the TV shows, "Pimp my Ride." Pimp this, pimp, it's in songs, everything is pimp, pimp, pimp, and so when these guys do that, you've got these screwed up girls who don't know any better and they'll think that it's cool and they'll hang out with them, and they'll start smoking with them and after that they'll say, "Oh you want to try it?" "Yeah, I'll try it."

Pimps operate mostly independently. Some operate in several cities, with a lot splitting time between Dallas and Oklahoma City, with a smaller number shuttling between Dallas and Miami and other prostitution hotbeds. Street gangs have attempted to get into the business but have proven to be pretty terrible at it. Another cop:

We've seen a couple gangs try it but the problem is with traditional prostitution when the gangs try it, they can't. When a pimp gets a girl, his job is to make money off of her, the sex is just a way to control her and make money. The gangs they get a girl in, they can't decide--do they all want to have sex with her, do they all want to do drugs with her, and generally what they do, is they all do sex with her, they all do drugs with her, and by the time they're all done, she's so messed up, you know they can only make 40 or 50 bucks. I just think that it's the whole structure of gangs that why they can't make that work. We don't see a lot of gangs on the kid side--now if they ever figured it out, we'd be in trouble.

More organized are the Asian massage parlors, which typically feature women from Thailand and the Philippines, some but not all of whom are trafficking victims. As one law enforcement officer puts it, the trafficking element is a hard thing to prove.

I think what we are really talking about is prostitution, and a very small percentage is being trafficked. It's not that easy to get to that point. Kind of like what I said earlier, they might have done it, they might have come over here from let's say China, they don't know what they are going to be doing, but they're kind of on the hook for the ride to get here. Then they get a massage license, maybe, then they start working in there, and it turns into prostitution and it changes once they get arrested. And they get out [once] they've paid off their debt, but then they come back to it, so it's prostitution. Trafficking aspect is very hard to prove because most of the girls don't want to do this, but some of them are happy to do it because they are sending money home.

There are also Hispanic-only brothels, which operate out of homes in poorer neighborhoods and advertise by passing out business cards that have only the word "construction" or "restaurant" and a phone number, and Russian-run strip clubs, which cops are aware of but have been unable to penetrate.

We've gotten complaints on them. [T]here was one club here, a nice one, they had Russians there ... and every time that we'd go up there looking we couldn't see what they were talking about ... it could have been that we just couldn't get in, none of us were Russian.

At the top of the local sex market are the high-dollar escort services that cater exclusively to a wealthy clientele, charging $500 or so per hour or $4,500 per night. One cop said these get little attention from law enforcement, both because the prostitution is typically voluntary and they don't have the resources to pay such high rates.

Also, there are truckers:

The truckers' thing is kind of its own undercover trucker network. And what they're doing basically is, it's gone pretty much online. And so they interact online and just give out a location of, "I'm going to be driving down I-10, such and such day at such and such time." And so then that's how they make the connection. They'll connect with the person actually along whatever route the person's driving through. Sometimes it's the husband helping to figure out what the wife's schedule is going to be.

The world's oldest profession isn't going to vanish anytime soon, or ever. The authors tell the Times they hope the report will give law enforcement a better understanding of the problem and help them rescue the most vulnerable victims.

Send your story tips to the author, Eric Nicholson.

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