"One Tree Hill" stars, crew accuse former showrunner Mark Schwahn of sexual harassment

Mark Schwahn attends "The Royals" series premiere on March 9, 2015 in New York City.

Neilson Barnard / Getty Images

Female cast and crew members of "One Tree Hill" are accusing former showrunner Mark Schwahn of sexual harassment. Eighteen women signed an open letter on Monday about Schwahn's alleged behavior during the show's run from 2003 to 2012. 

The women said they were penning the letter, which was published in Variety, in support of their colleague, Audrey Wauchope. Wauchope now writes for "Crazy Ex-Girlfriend" but used to write for "One Tree Hill."

On Saturday, Wauchope posted a string of tweets about the showrunner on her first job, and how she was told that he hired female writers based on their appearance. Wauchope said that this showrunner massaged his female employees' shoulders, touched their hair, put his arms around them, showed male staffers naked photos of his girlfriend and tried to talk Wauchope's writing partner, Rachel Specter, out of getting married so he could date her. Wauchope said, "I know he did more but not to me so they're not my stories to share." She also added that he did not attend the mandatory sexual harassment training at work. 

Though Wauchope did not name Schwahn, she made it clear she was talking about "One Tree Hill," saying that while she and Specter wrote for two shows together, their male colleagues on "Cougartown" were "aces." 

Eighteen women who worked on "One Tree Hill" -- including stars Sophia Bush, Hilarie Burton and Bethany Joy Lenz -- said in their letter, "To use terminology that has become familiar as the systemic reality of sexual harassment and assault has come more and more to light, Mark Schwahn's behavior over the duration of the filming of One Tree Hill was something of an 'open secret.' 

"Many of us were, to varying degrees, manipulated psychologically and emotionally. More than one of us is still in treatment for post-traumatic stress. Many of us were put in uncomfortable positions and had to swiftly learn to fight back, sometimes physically, because it was made clear to us that the supervisors in the room were not the protectors they were supposed to be. Many of us were spoken to in ways that ran the spectrum from deeply upsetting, to traumatizing, to downright illegal. And a few of us were put in positions where we felt physically unsafe. More than one woman on our show had her career trajectory threatened." 

The women also wrote, "Many of us were told, during filming, that coming forward to talk about this culture would result in our show being canceled and hundreds of lovely, qualified, hard-working, and talented people losing their jobs."

The letter closed with the line: "Believe Women. We are all in this together."

Just last month, Burton tweeted about when Ben Affleck groped her on "TRL" in 2003. Affleck apologized. 

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