Josey Aimes is based on Lois Jenson, who started working in the mines in 1975 and endured thirteen years of harassment before filing her first lawsuit. Jenson v. Eveleth Mines was settled in 1998, ten years after it was first filed, and over twenty years after the harassment began.
Charlize Theron wanted to react to the crowd in the Union meeting without rehearsal, so it would feel authentic. Because the heckling was unscripted, it took Richard Jenkins almost five minutes to quiet them. Theron was so uncomfortable during this scene, she broke out in hives. "That was, I think in my entire career, the most devastating thing I've ever encountered."
Some of the women standing up in the last courtroom scene were real plaintiffs.
In real life, there were multiple trials, not just the one depicted in the movie. In the first trial, Jenson and two other women petitioned to have the lawsuit designated a class action, on behalf of all women working in the mines. The judge certified a class action including only the hourly female mine workers, not the salaried female officer workers who were also sexually harassed. The second trial established that sexual harassment occurred and that the company was liable for it. The third trial was to determine the amount of monetary damages each woman suffered. The fourth trial, in the 8th Circuit Court of Appeals, reversed the award of damages. The company settled just before the fifth trial started, paying each plaintiff an average of $233,000. By the time Jenson received compensation from the company in 1999, her children were grown and she was too disabled to work.
When Sherry (Michelle Monaghan) is trapped in a portable outhouse by her male co-workers, who rock it and tip it over, the human waste was made of Gatorade, Cocoa Puffs, and pumpkin pie filling.