Despite the fact that for the past year Massachusetts has been armed with a new law to crack down on human trafficking and the people who pay for sex, a New England Center for Investigative Reporting report found that most men arrested in Suffolk County for buying sex, known as "johns," get their charges dropped. This is part three in a four-part series on the challenges police encounter when going after "johns." Read parts one, two and four.

In an unmarked SUV — the color of which blends with the night — Lt. Stephen Haberek drives along rain-drenched Union Street looking for signs of illicit activity in downtown Lynn.

"The same car passed me ten times," Haberek said. "There’s no reason for it."

Haberek heads the city of Lynn's Special Investigation Unit responsible for taking on drugs, guns and sex crimes.

"This is a heavily trafficked area," he said. "People drive by. You typically wouldn’t find prostitutes on a dead end. You wouldn’t find them out of the way. You find them where traffic is going to come by. Johns, they’re used to coming by this location."

Haberek loves his work and he loves this town.

"Growing up in the city and being part of this city, I’d like to do what I can do to give Lynn its due," he said.

That drives his ambition to stamp out the street prostitution and related vices that have given Lynn a reputation in the underground trade — drawing in undesirable elements to this city who feed on a smorgasbord of taboos.

"They drive up and they find somebody, you know, down on their luck, out there working the streets for a drug addiction," Haberek said. "That’s not all the girls, but I would say that’s a lot of them. I’m not going to head to Marblehead or Wellesley to find a prostitute. They come to Lynn. But you know, we try really hard so that they don’t want to come to Lynn."

Over the past year, Lynn has been doing what many other municipalities across the state are not: Police are arresting men who solicit sex in greater numbers than the girls and women who are being prostituted on the streets."

"Prior to my coming on — this is the old vice unit: prostitution, gambling, alcohol, drugs — I know they were very active under the previous commander," Haberek said. "I’m sure they had impressive numbers as well."

Impressive numbers, yes, but as is often the case, lopsided numbers. In 2012, 75 women were picked up, but only 10 johns found themselves in handcuffs. A year later, when Haberek took over the unit, police stepped up john stings. There have been five on his watch.

"You can’t depend on conducting one and then being free of the problem," he said. "It’s going to creep back. If we have a girl working on the street and my detectives can go out and they’re able to find that there is an agreement for sexual conduct for a fee, then the person is arrested. It could be male. It could be female. But we recognize that these john laws are effective so we also arrest the johns."

Lynn’s roundup of 92 men accounted for 63 percent of prostitution-related arrests in 2013, according to state records. In that same year police arrested 55 women. Fifty-seven miles away, NECIR and WGBH News uncovered a picture on the streets of Worcester that is a complete statistical reversal of the current scene in Lynn: In Worcester last year, by one count, only three men were arrested for soliciting prostitutes.

And those three people were arrested in January of 2013. That’s it.

Marianne Sarkis, a professor of social movements at Clark University in Worcester, repeats the number three in astonishment.

"That’s all we had for 2013!" Sarkis said. "If we’re not looking at specific patterns in the data; if we only look at 2013, that’s a disturbing finding."

Worcester stands out among other Massachusetts cities because it is the only community statewide that has what is called a "john school": a court-mandated program to encourage behavioral change in men who solicit sex. But here has not been a john-school class since September 2013 because there are no arrests.

"They have to be arrested to get sentenced to john [school] or to have that option," said Athena Haddon, program director for Everyday Miracles Peer Recovery Center.

NECIR crunched the numbers and found that the arrests of prostituted women in Worcester nearly doubled from 87 in 2012 to 157 last year. Police say they arrested 14 men in 2013. Most critics say the number is only three. The year before it was 31 john arrests. So far this year, only five men have been arrested for soliciting compared with 113 women, according to the Worcester Police Department.

Why the gender disparity?

"It’s the million-dollar question," said Haddon, who is also a member of Worcester’s Demand Abolition coalition.

"We don’t know why it’s not happening," she said. "The difference in the arrests for the women and the men is disturbing, that they’re not being arrested at the same rate."

Worcester Police Chief Gary Gemme is not very vocal about this disparity. His office declined to comment specifically on arrest numbers, but in a written statement to NECIR he noted that his force generally focuses on “reducing the visible presence of prostitution-related activity that negatively impacts the quality of life in our neighborhoods.”

And what is the impact on quality of life?

"I had a woman who contacted me on email and she said she put her trash out one night and a guy pulled over and propositioned her," Haddon said. "She was outraged. She spoke to other women in her building and it had happened at some point to every woman in her building."

Sarkis and others say advocates need to sit down with the police and city officials to find out what happened between 2012 and now to determine what led to the glaring disparity between the arrests of prostituted women and their solicitors. Some point to the economic downturn in Worcester that resulted in police layoffs and a temporary freeze in hiring. That may have led to a decrease in total arrests, but it doesn’t explain the disparity.

The kind of police operations that are mounted in order to catch johns may offer a clue.

In Lynn, "We have a female officer pose as a prostitute and the johns come up and solicit sex for a fee and they’d be arrested," Haberek said.

In Worcester, advocates say police expressed reservations about this kind of operation.

"We heard it puts a police officer at great risks," Haddon said. "My argument to that is, when you join the police force you know it’s a great risk. There have been in the past some well planned-out stings, including one where there was a two-day sting and 58 men were arrested in Worcester. That was a well thought-out police sting. We’ve heard arguments that the johns are too smart. That the female officer can’t get into the car, and if they can’t get into the car, [the johns] drive off."

It is dangerous, and no one knows that more than prostituted women themselves. One woman who asked not to be named was recently interviewed for Clark University's oral history of prostituted women in Worcester.

"He had the knife pressing upside my throat and all of a sudden I was screaming, I was crying," the woman told the project. "I said, 'Please, don’t hurt me.' And so he said to me, 'You like this? You like what you do? The anger that I heard in that man’s voice and I never thought I was going to make it out that car."

In Worcester, day or night — you can drive down Main Street, as I’m doing now, and the telltale signs of The Life can be spotted at bus stops, in front of vacant lots and bustling stores, as drivers slow down to ask “how much.”

"Me and the guy was sitting in the car and he had his clothes off and we was sitting there talking," the woman said. "And that was his fetish. I still had all my clothes on. The cops came by and told him to pull his clothes up and arrested me."

Sarkis heads up the Clarke program.

"All of them, almost all of them would cry during the interview and say, 'I hate this life, I hate this life, I don’t want to be there, but what choice do I have?’" Sarkis said. "That’s not a choice narrative. You don’t hear that from people who say ‘Yeah, I’m choosing to do X, Y and Z.’ And that’s why it’s important to hear women's voices, because the men are not hearing them."

The joint WGBH News/NECIR investigation comes four years after Massachusetts lawmakers passed a law that increased fines and jail time for sex buyers. But the efforts haven't had an impact statewide, according to data analyzed by the NECIR. It reveals nearly 70 percent of the 920 arrests on prostitution-related charges in 2013 were of women. Massachusetts anti-trafficking law gives police more latitude in arresting johns and cracking down on pimp-controlled or coerced prostitution. But in Worcester and Lynn, we see two different results over the past year.

In Worcester the onus is still on the woman, says Robin Curry, a member of the Citywide Advisory Committee on the Status of Women.

"The culture has to change the ways of law enforcement and we’re trying to get that vision in their heads," Curry said. "We started out because the police department was putting the addresses of women, after they were arrested, on Facebook and then these women were being visited, accosted and having letters from convicts, and all type of bad things were happening. So we got together and we wrote a policy and we presented it to the police and the city manager and within 24 hours they adopted that policy that they would no longer do that."

Along the Massachusetts Turnpike and part of the away along 95 north toward Lynn, I’m listening to a John Legend track, "Take Me Away,” a song about a woman trapped in The Life. It’s the kind of woman, Haberek, on patrol hours later, says he’s arrested more times than he would have liked.

"We don’t want the girls out here," he said. "And that’s why we’ll target males. We don’t want them, up and down here. These shops trying to do business, they don’t want somebody standing out in front dropping needles or going behind their business doing their business."

I ask: even on a chilly night like this?

"Yes, wintertime, summertime," he said. "It really doesn’t matter."

It’s a quiet night. Haberek checks on his detectives and then responds to a heroin overdose at a hospital. After leaving the facility, he steers his unmarked SUV along the usual cruising avenues, looking for drivers, who are looking to score.

"We’re not just shifting our problems to other cities," Haberek said. "We’re dealing with it. And if other communities deal with it as well, hopefully it will have an impact on the overall behavior. And that ultimately is our goal."

Meanwhile, in Worcester, the rain on this day has not deterred whatever spurs men to drive slowly up and down Main Street. Anti-human-trafficking advocates are holding a rally on this avenue on Wednesday, October 8, to try to get police and city officials to do what a driving rain cannot: discourage men from buying sex from desperate women and to try to put a dent in the underground trade.

This story was produced with our partners at the New England Center for Investigative Reporting, a nonprofit news outlet based at Boston University and WGBH News.