From the street, the little brown house was unremarkable yet pleasant. A bright yellow toy school bus and red truck hung on the hog-wire fence, and the home’s facade featured a large Texas "Lone Star."

But in the backyard was a gutted mobile home that a prosecutor later described as a "house of horrors.” It was discovered one day in 2014, when a man called from Maryland to report that his stepfather, Moises Ferrera, a migrant from Honduras, was being held there and tortured by smugglers who had brought him into the United States.

His captors wanted more money, the stepson said, and were pounding Ferrera’s hands repeatedly with a hammer, vowing to continue until his family sent it.