Considering that every action taken by these companies was illegal, I don't know what you mean by "the law that enables companies to abuse". I'm actually deeply in favor of immigration reform in the US, but human trafficking is not created by the law, it is blatantly illegal. The illegality doesn't even begin in this case in the article with the US, but with the coyotes in India that charged these men $20k USD for them to come to the US to work, when in fact legally it should be the other way around, the visa sponsoring entity cannot charge you for relocation costs, and may pay for them (but is not required to do so).