Half a million women in this country work in the farm fields. Many of them are undocumented, working below the radar and without the protection of law enforcement.

In "Rape in the Fields," PBS' "Frontline" examines case after case of female farmworkers coming forward about being raped, sexually assaulted and sexually harassed by their supervisors. The issue of sexual demands amid the almond groves, strawberry farms and lettuce fields is so pernicious that women have come up with the names "the green motel" and the "field of panties."

"Rape in the Fields" premieres on PBS next Tuesday and, in a unique collaboration, on the following Saturday on Univision as "Violación de un Sueño" ("Violation of a Dream"). Frontlline also partnered with the Investigative Reporting Program at UC Berkeley, and the Center for Investigative Reporting to produce the project.

"Frontline," the premier public affairs program, looks at cases where an Iowa egg farmer paid out a $1.3 million settlement to 11 women workers but accepted no responsibility. We hear from the county sheriff who expresses frustration over the failure of any law enforcement agency to follow up on the women's claims for criminal charges; from the district attorney, to the FBI, to immigration. It follows a 2006 lawsuit by 26 women against their supervisor at a fruit plant in Washington. A jury this year threw out all their claims. It examines the case of a woman who said her supervisor at a farm in Fresno County raped her three times, once at gunpoint, but was never criminally charged.

Before 1995, no government agency was responsible for protecting the plight of migrant and seasonal farm workers. Even today, fearful that coming forward might jeopardize their jobs — and their stay in this country — many women remain silent, even though in 2005 Congress authorized the U visa, which gives victims of certain crimes temporary legal status and work eligibility in the United States for up to four years.

Their fear? "One phone call and you'll be deported," said U.S. Rep. Luis Gutierrez, D-Illinois, chairman of the Immigration Task Force of the Congressional Hispanic Caucus.

Mark Brunswick • 612-673-4434