CHICAGO (CBS) -- Sex trafficking is a complicated problem that for many reasons is difficult for law enforcement to address and enforce.
But as CBS 2's Joe Donlon found as he rode along for a sting operation earlier this summer, those challenges are not stopping efforts to fight trafficking. The Cook County Sheriff's office is even using survivors to intervene.
We were behind Cook County Sheriff's police as they pulled over a driver. It looked like a typical traffic stop, but it was not for a traffic violation.
Rather, the driver had just left a brothel in Chicago's Bridgeport neighborhood, and sheriff's police officers had been watching. What Sgt. Timothy Hannigan and his team really wanted was information.
"How to get in; what do you got to do when you get in? Who do you pay? What do you got to pay? Is there any secret word? Is there a secret text message you've got to send to get in there?" are the questions to which police want answers, Hannigan explained.
The people who are pulled over do talk to officers – and tell them everything, Hannigan said.
"Usually, they're nervous, and then, they don't want to get caught up with their wife," Hannigan said. "So we talk to them. We just ask them if they'll cooperate with us, and they do."
Hannigan told Donlon the Sheriff's police had been watching the Bridgeport brothel for two and a half weeks. The next step was to shut it down.
Joining a raid for the first time, was Pamela Nicole Dukes. She joined the Cook County Sheriff's Police Special Victims Unit in January.
Donlon: "What is it about this that drew you to this job?"
Dukes: "There are a number of things that drew me to this job. Again, I keep no secrets. I am a survivor – domestic violence, human trafficking – and that kind of made me say yes to the job."
For Dukes, it's personal. She is on the support side of the team – stepping in to offer services to the women being trafficked, or basically, to rescue them.
"So like, they don't have passports – their passports have been taken away – or they're being threatened in some way, shape, form, or another," she said.
Dukes explained that the women being trafficked usually cannot just walk away from the situation.
"Most times, no," she said, "because there's something tied to their liability or the liability of the people they love."
More than a dozen officers were involved in the raid. An undercover officer went in first – to finalize an earlier online transaction in person.
The undercover officer was able to get in without ringing the doorbell.
Donlon: "Why do you have to wait for him to make the deal? Hasn't the deal already been made online?"
Hannigan: "You don't know who's behind that message."
That will actually become an issue in this case.
Right afterward, the officers went in – announcing themselves as police and ordering everyone to come out. Two people ran out the back door to get away, but officers were ready and waiting.
Meantime inside, there were two women. One started to cry as an officer talked with her – explaining to her that she was not in trouble.
The woman did not speak English, so the officer spelled it out – using her phone to translate.
Overall, sheriff's police thought the operation went very well.
"As soon as we opened the door - there was a side door that I had officers over on standby. So as soon as we opened the door, the male and the female – the doorman and one of the females - took off," Hannigan said.
The team took four people in for questioning. But what seemed like a textbook case took a twist weeks later.
The Cook County State's Attorney's office said it needed more information before bringing charges. Cook County Sheriff Tom Dart could not understand it.
Dart: "This is one – as a former prosecutor I can just tell you – I'm befuddled we didn't get charges."
Donlon: "That's the basic question – how do you take a brothel down and no one gets prosecuted?"
Dart: "I don't have any explanation whatsoever. The explanations I've been given so far – none of them make any sense."
Since 2017, the county says its vice unit has taken down 15 brothels. A total of 18 people were charged.
Of those 18, six were convicted of promoting prostitution, three are still awaiting trial, and nine – or half of them all – had charges dismissed.
"This case – everything was there. There's no like, 'Well, we're missing this or this.' No, we have real victims. We have people we took into custody at the scene. We have people who are identifying them and their roles involved with this," Dart said. "So there's no missing element in this."
Meanwhile, with the raid over, the work began for Dukes. She offered support to the two women inside the brothel.
Neither of the women will face charges, and both were able to leave for their home states.
It is an example of the Cook County Sheriff's Office's focus with trafficking and the sex trade – helping the women get out.
The Chicago Alliance Against Sexual Exploitation would like to see more of the same efforts from the Chicago Police Department. CAASE has analyzed prostitution-related arrests over time, and one study found that in 2017, 90.9 percent of arrests by Chicago Police were for "selling" offenses – in other words, the women.
Only 8.2 percent of arrests by Chicago Police were for buying or soliciting, while 0.5 percent were for other related offenses.
The county is trying to address that. It created a victims' support services unit last year, and has already helped 136 victims obtain services and support.
"And that's so heartening to us," Dart said. "Yeah, sure, it's not this macro thing where we've ended it all – no – but we have these little success stories that keep reminding us why we do this."
"I don't think that when we take this down, it's the end of it at all," Dukes added. "The work continues."
Dukes told us one victim said, "No one out here is worrying or cares about me."
Dukes told her, "We beg to differ."
Meanwhile, the fact is everyone on the details knows the work continues.
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