Valedictorian's mic is cut off as she starts to mention alleged sexual assault on campus

A valedictorian was cut off as she began to mention alleged sexual assault.

Lulabel Seitz, 17, was silenced during her graduation speech when she says administrators from Petaluma High School realized she was about to talk about alleged assaults -- including one against her -- and the treatment of victims.

Seitz, who will be attending Stanford University in the fall and double-majoring in applied mathematics and economics, said she wasn't going to raise the issues -- until administrators specifically told to keep it out of her speech.

"They made all these rules to prevent me from speaking," Seitz told ABC News in an interview Saturday. "So I decided to use the opportunity to bring it up."

Even before graduation, Seitz said officials from the school were putting pressure on her to avoid any mention of the alleged assaults. She said she was pulled out of her last class in high school to make sure she got the message.

"They told me to be quiet, told me I can't talk about it," she said. "I realized that this is a big injustice and needs to be spoken about."

So about four minutes into her speech last Saturday, just as she was about to mention the alleged assaults, Seitz said administrators cut the mic.

Some in the audience at the outdoor graduation ceremony chanted, "Let her speak!"

Undeterred, Seitz kept going.

"I just finished my speech without a microphone," she said.

Seitz later recorded her full speech and published it on YouTube. The video, which shows the moment she was cut off while speaking at graduation, had been viewed more than 45,000 times as of Saturday afternoon.

Seitz added that she wasn't surprised by the school's alleged attempt to keep her quiet.

"This is what they've been doing," she said of the school. "I thought that maybe for once, they would let a student speak up."

ABC News reached out to Petaluma High School but did not immediately hear back Saturday. The Petaluma City Schools, however, provided a statement.

Seitz told ABC News that she emailed the superintendent of the district, Gary Callahan, but had not heard back as of Saturday afternoon.

One of the alleged assaults Seitz planned to bring up during her speech was an attack she says happened to her last fall. She said a student assaulted her on school grounds.

But administrators didn't suspend or expel the student, she said, and instead encouraged her to drop it.

"They told me not to speak about it," Seitz told ABC News.

Seitz said the incident was reported to police and the student, whom she didn't name, was arrested.

ABC News reached out to the Petaluma Police Department to confirm the incident and arrest but not did immediately hear back Saturday.

Still, Seitz said throughout the process, administrators appeared to want to protect themselves, and not students.

"Throughout my whole case, the administrators told me their jobs were on the line," she said. "They put their jobs before students, which is not how it should be."

ABC News' Wil Cruz contributed to this report.