The accusations come more than five years after the show's conclusion, amid a reckoning in Hollywood during which people from across the industry are speaking up about instances of alleged sexual assault or harassment.
"One Tree Hill" ran for nine seasons from 2003-12, first on The WB and then on The CW.
The letter stated that women on the show were "manipulated psychologically and emotionally".
Two days after those online networking posts, One Tree Hill performing artists Sophia Bush, Hilarie Burton, and Bethany Joy Lenz, alongside numerous others, posted a joint letter blaming the showrunner for provocation. 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.
"Huge numbers of us were addressed in ways that ran the range from profoundly irritating, to damaging, to out and out unlawful", the letter proceeds.
In addition to calling her time on One Tree Hill demoralising, she cited instances where Schwahn showed staffers naked photos of an actress he was in a relationship with without her knowledge and tried to convince Wauchope's writing partner, Rachel Specter, to call off her wedding and date him instead.
Schwahn's representatives have yet to issue a statement regarding these allegations.
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They also created a "reflective" video from an aging millennial who recalled what happened because of the promotion. By now, you've heard of President Donald Trump's plans to build a border wall at the U.S. -Mexico border.
E!, the network that now hosts Schwahn's show "The Royals", also released a statement, writing, "We are monitoring the information carefully".
"To say we left that job demoralized and confused is also an understatement. E!, Universal Cable Productions and Lionsgate Television are focused on giving a protected workplace in which everybody is dealt with deferentially and professionally".
On social media, the former cast and crew who signed the letter were met with support by other fellow cast mates.
"I applaud every woman on OTH, every woman on earth, who stands up to a system that has failed them in the past and in this moment".
The women were inspired to make a statement after a writer on the show tweeted about an unnamed showrunner who harassed female writers. In her messages, she accused the showrunner of inappropriately touching her, making inappropriate comments and even allegedly showing off nude pictures of his actress girlfriend. "Furthermore, a couple of us were placed in positions where we felt physically hazardous". He pet hair. He massaged shoulders. "It turns out my story was a catalyst for others and I stand by them as they continue to speak".
The cast and crew members who wrote the letter supporting Wauchope said they are all "deeply grateful for Audrey's courage". "We also understood that no one was fully unaware [of what was happening on the set]", they continued.