Jana Kramer is one of a number of ex-One Tree Hill cast members and crew members accusing showrunner Mark Schwahn of sexual harassment. The singer and actress played Alex Dupre during later season of the TV drama, which was on air from 2003 through 2012.

On Saturday (Nov. 11), via Twitter, writer Audrey Wauchope recounted being sexually harassed -- along with her writing partner, Rachel Specter, and other women -- by the showrunner at her first TV writing job. She did not specifically name Schwahn or One Tree Hill, but fans and media outlets were able to identify him and the show. After some of the show's stars tweeted support of Wauchope, they and even more women involved with the show penned a letter to Variety further explaining the allegations.

"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," the letter reads, in part. "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."

Collectively, the women explain that they supported and "confided in" each other during that time: "We set up safe spaces to talk about his behavior and how to handle it. To warn new women who joined our ranks," they write, also noting that while "no one was fully unaware," they know that much of what went on "[was kept] out of sight for the studio back home."

The letter, which ends with a call for change, is signed by 18 cast and crew members, including Kramer. ET reports that a number of the men who worked on One Tree Hill have also stepped forward in support.

Schwahn currently acts as showrunner for The Royals. In a statement, the companies behind that show say they are "monitoring the information carefully" and "are committed to providing a safe working environment in which everyone is treated respectfully and professionally.”

Kramer has previously spoken out about another case of sexual harassment she faced early on in her acting career, when a former agent nearly drove her out of the business. A talk with her mother convinced Kramer to fire him and keep fighting.

Kramer has overcome some painful hurdles in her personal life as well: She was in a physically and emotionally abusive marriage to Michael Gambino and dealt with her husband Michael Caussin's infidelity. However, Kramer has tackled those moments with grit, tenacity and transparency.

“I love empowering women, especially women that need help and encouragement, to make them feel better and make them feel beautiful,” Kramer says. “I feel like women can be just brutal to each other ... So to be able to empower women to have a voice, to be able to speak out and to be confident with themselves and not to have to settle for anything and feel like that’s what they deserve, is just wonderful to be a part of.”

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