While their suits are rare, they are not without precedent. In 2014, a court in Huelva, Spain, found three men guilty of an “offense against moral integrity and sexual harassment.” Their victims were Moroccan women who worked for them in 2009. An article in El País in 2010, “Victims of the Red Gold,” documented a series of sexual allegations by Polish and Moroccan workers.

In response to criticism in the news media last fall, the Spanish government promised to implement safeguards for this season, and the Moroccan minister of labor has also promised improved conditions. But the workers and unions say little or nothing has changed.

Moroccan officials, including the minister of labor and the ambassador in Madrid, Spanish officials, and several representatives of farming associations, declined to comment for this article, as did the owner of Doñaña 1998 d’Almonte.

“Our work stops in Tangier — beyond, it becomes a Spanish affair,” Noureddine Benkhalil, a manager at ANAPEC, the agency that recruits the women in Morocco, told a local TV network last year.

In an email, a commission spokeswoman at the European Union said that it did not tolerate labor exploitation but said Spain was responsible for addressing the issue.

The women say they are determined to see their cases through to the end. The initial whistle-blower, H.H., tries to keep spirits up. Whenever one of the women breaks down, she reminds her that it was their duty to speak so that others could work on these contracts without fear.

“I will never let it go,” H.H. said. “I already lost everything. I have nothing to lose. I will fight until I die.”