Federal prosecution of new criminal cases involving human trafficking in Minnesota and Wisconsin remained steady or dropped slightly from 2017 to 2018, according to an international organization tracking such numbers.

The Human Trafficking Institute, based in Fairfax, Va., released figures Wednesday from its 2018 Federal Human Trafficking Report. The report tracks new and active trafficking cases working their way through the nation’s federal court system, as well as convictions in those cases.

For 2018, federal prosecutors brought indictments in two new trafficking cases in the District of Minnesota, while Wisconsin’s two judicial districts saw five new cases.

Nine cases in all were active in Minnesota in 2018, and 16 in Wisconsin. Of the new and active cases in Wisconsin last year, just one each were brought in the Western District of Wisconsin, which includes portions of the Northland.

The numbers aren’t a significant departure from 2017, when Minnesota had two new cases and 11 active cases and Wisconsin had six new cases and 14 active cases.

One conviction was obtained in Minnesota last year, while Wisconsin had six convictions. In 2017, Minnesota saw five convictions while Wisconsin had two.

Of Minnesota’s active cases in 2018, 77.8 percent were sex trafficking cases, while 22.2 percent involved labor trafficking, such as domestic servitude or forced food service, agricultural or construction work. In Wisconsin, 93.7 percent of cases involved sex trafficking, while 6.3 percent involved labor trafficking.

Human trafficking is difficult to track because cases often go unreported, said Kyleigh Feehs, associate legal counsel with the Human Trafficking Institute and co-author of the institute’s 2017 and 2018 trafficking reports.

The institute began tracking the cases only in 2016, so only three years of data are available so far. In addition, the report only focuses on cases prosecuted in federal court. Availability of data from state courts — and the ability to narrow that data down to specific crimes — varies greatly by location. Researchers deemed the task too daunting for now, Feehs said.

Feehs also said trafficking cases often intersect with interstate commerce, and when traffickers or other involved parties or materials cross state lines, those cases are tried in federal court.

So, while the institute’s report is readily available, the numbers don’t necessarily tell the whole story. But the institute’s goal isn’t to document the prevalence of human trafficking in the United States; rather, it aims to track the federal court system’s response to known cases.

“(The number of cases nationwide) is just a really hard number to know, due to the nature of this crime; it's a hidden crime,” Feehs said. “So we started thinking, OK, that number, it's hard to know with accuracy, but why can't we count numbers that we can know?”

Nationally, of 771 active human trafficking criminal cases in 2018, 67.8 percent involved sex trafficking of children, while adult victims were involved in 32.5 percent of cases. Sex sting operations with no victims made up 8.4 percent. Labor trafficking cases made up 5.1 percent.

The number of new trafficking cases nationwide dropped by 29 percent from 2017 to 2018, from 241 to 171. However, prosecutions have risen sharply since 2000, the year that the federal Trafficking Victims Protection Act was signed into law. That year, just four cases were initiated in federal court.

Feehs cited the April 2018 closure of Backpage.com, a classified advertisement website long known for offering paid sexual services, as one possible reason for the drop in prosecutions. Another factor could be shifting immigration policies as authorities focus more on drugs or gangs, she said.

Federal prosecution of labor trafficking cases, meanwhile, have remained relatively stagnant, and that’s a problem, Feehs said.

“I just think that's really fascinating, because from the numbers globally, there's a much higher percentage of labor trafficking than sex trafficking,” she said. “But we're failing to identify and to prosecute those cases.”

Feehs highlighted that Minnesota and Wisconsin are two of only 20 states with active labor trafficking cases involving labor trafficking.

While the institute was founded by former U.S. federal prosecutors and maintains a strong relationship with the Justice Department, much of its work is focused abroad, particularly in Belize, South Africa and Uganda.

The institute aims to provide statistics but leaves the interpretation to others. However, Feehs said, as the institute continues to monitor federal prosecutions, the numbers will tell a clearer story.

Wednesday’s report comes in the wake of the March arrests of Shuangyan Yang and her husband, Michael Shykes, who allegedly recruited women to provide sexual services to clients at the massage parlors they ran in Duluth and Superior.

The two face sex trafficking and racketeering charges after police conducted an 18-month investigation. Both are due in court for hearings on July 16.