Federal Lawsuit in Arizona Puts Spotlight on Guest Workers Listen Download Embed Share Share this on Facebook (Opens in a new window) Share this on Twitter (Opens in a new window) Share this via Email In this May 10, 2011 file photo, field workers pick onion bulbs on a Vidalia onion farm in Lyons, Ga ( David Goldman / Associated Press ) Produced by Rob Gunther Hosted by Todd Zwillich Produced by PRI and WNYC