In the past few years, nearly 200 people reached out for help to the National Human Trafficking Hotline to report forced labor — but new reporting from the GBH News Center for Investigative Reporting found that number is likely a massive undercount. Victims of forced labor are likely all around us, working as janitors, in restaurants and as domestic workers.

Reporter Sarah Betancourt and Deputy Investigative Editor Jenifer McKim joined Boston Public Radio Wednesday to explain how they reported the series and why so many of these cases of abuse go unpunished.

"[When] we see people who are working, it's hard to see if it's a crime," McKim explained. "And basically, forced labor means that people are working without pay or underpaid, being under some type of force or threat or fear. And we found that there's many, many folks in the state where this is happening."

Even victims are not always sure whether anti-trafficking law applies to them, and in some cases where they have lodged complaints against foreign abusers, the defendants have simply left the country to evade prosecution.

Betancourt said that the federal government provides a special visa for victims of trafficking, but it is dramatically underused.

"This is protection that allows them to remain in the U.S. legally with work authorization for four years. And you could also get a pathway to a green card. So that's the silver lining," she said. "But unfortunately, right now there is a 40% denial rate, a really long wait time of over a year."