NPR recently ran a three-part series about the "House of Death," in which U.S. Immigration and Customs Enforcement agents refused to close an investigation into a drug operation despite becoming aware of and having the capacity to prevent a number of gruesome murders, some of which were aided by one of their informants, who went by the name of "Lalo." (Prior Reason coverage of the story here.)
I reported last March that the federal government has been trying to deport Lalo back to Mexico, despite knowing that he'll almost certainly be killed. According to NPR, the deportation proceedings haven't yet been resolved, and Lalo is still in solitary confinement—not for his crimes in Mexico, but because the U.S. government no longer needs his services as an informant, and now considers him an illegal alien.
Last May, I interviewed Sandy Gonzalez, the DEA agent who blew the whistle on the House of Death—and lost his job because of it.