SASABE, Arizona -- Tim Foley lights his cigarette in a drab and musty abandoned home near the U.S.-Mexico border, where he spends his days and nights hunting for drug traffickers and undocumented immigrants. His desktop PC shows an aerial satellite map of the region with a red, vein-like web of the secret paths and trails that he's spotted Mexican cartels using to send hundreds of pounds of heroin, cocaine, methamphetamines and marijuana right through his backyard and into the United States.
