Aniya Harmon, 18, said she was distraught when she discovered in May that a rumor going around Sussex Central High School was true: Someone had created a meme that showed her nude breast and had shared it with school employees.

Ms. Harmon and her mother, Tosha White, said in interviews that they later learned a disturbing detail. Two principals at the school in Sussex County, Del., they said, had used security camera footage to make the meme, superimposing Janet Jackson’s face on Ms. Harmon’s in a reference to the exposure of the singer’s breast during the 2004 Super Bowl halftime show.

The mother and daughter detailed their claims in a lawsuit filed this week in Delaware Superior Court in New Castle County against the former Sussex Central principals, Bradley Layfield and Matthew Jones, who have been placed on administrative leave.

On May 17, a teacher who was trying to break up a fight accidentally pulled Ms. Harmon’s jacket and bra strap, exposing her breast. Ms. Harmon and Ms. White claim that the two principals then reviewed security footage, created a still image of Ms. Harmon’s nude breast and shared the meme with faculty.

They also claim that Mr. Layfield shared the unedited video with other faculty members. The family is asking for criminal charges to be filed against both men. The Delaware State Police and the Sussex County prosecutor’s office did not respond to requests for comment on Friday night, but a lawyer for Mr. Layfield said that the state police were investigating.

“I’m still disappointed,” Ms. Harmon said on Friday. “And I’m still in shock about everything.”

The high school and the Indian River School District, which were also named as defendants in the lawsuit, did not immediately respond to calls seeking comment on Friday. Messages placed to phone numbers and emails listed as belonging to Mr. Jones were not immediately returned on Friday night.

Mr. Layfield’s lawyer, Thomas S. Neuberger, said in an interview that his client had reviewed security footage of a fight that broke out at school involving Ms. Harmon. But Mr. Neuberger denied that Mr. Layfield shared that footage — or still images and memes of the moment Ms. Harmon’s breast was exposed — with anyone via email or phone, adding that the file size of the footage was too large.

Mr. Neuberger said that Mr. Layfield, who was head principal, had been reviewing footage on the day of the fight in his office and had shown it in person to state troopers, assistant principals and some teachers.

“This is in accord with custom and policy in keeping the peace in the schools,” Mr. Neuberger said.

He said that the meme was created and shared solely by Mr. Jones, who was an assistant principal.

“I do not know the answer to the question of when my client learned that there was a meme that had been created by this guy,” Mr. Neuberger said.

Emeka Igwe, a lawyer for Ms. Harmon’s family, said on Friday that the school resource officer, “the one designated person who potentially could have seen the video for safety reasons,” was not shown it. Instead, he said, gym teachers and “other males who had nothing to do with this” were shown the video.

The lawsuit states that Ms. Harmon was not involved in the fight that broke out on May 17 and had only told a student who had been yelling at a boy to “quiet down.” As the student screamed at Ms. Harmon and “bucked at her threateningly,” a teacher stepped in and pulled at Ms. Harmon’s clothes, exposing her breast. Mr. Neuberger claims that security footage shows Ms. Harmon was involved more directly in the fight.

The suit claims that Mr. Jones showed the meme to vice principals, administrators, teachers and others on his school-issued laptop, and that he had worked with Mr. Layfield and “possibly others” to create it.

“Mr. Jones and Mr. Layfield knew or should have known that the data they possessed and shared contained private and confidential information and content, including sensitive and private photographs and video of plaintiff’s exposed breast,” the lawsuit states.

At least six people, the suit states, had images of Ms. Harmon’s breast because of Mr. Layfield’s and Mr. Jones’s actions.

Ms. White, Ms. Harmon’s mother, said that she heard rumors about the meme from people who worked in the school district or in neighboring ones, suggesting that many people were aware of it.

When a school official called Ms. White days after the fight to confirm that her daughter’s breast had been exposed at school on May 17, the official did not say anything about a meme or that the footage had been shared or seen by other faculty, Ms. White said.

Ms. White and Ms. Harmon learned about the meme on May 19. The principals were placed on administrative leave on May 22, according to Mr. Neuberger.

“I was in shock for about four to five hours,” Ms. White said. “And then once my shock came down, I was infuriated. I was angry, and I’ve been angry ever since.”

Mr. Neuberger said that the Delaware State Board of Education had informed Mr. Layfield in May that it was investigating him and that his education license might be revoked. Mr. Layfield was also not allowed to be at the podium at graduation to distribute diplomas, Mr. Neuberger said.

The episode, Ms. White said, had ruined what was supposed to be a celebratory time for Ms. Harmon right before her high school graduation.

Ms. Harmon, now a college freshman majoring in business, said that in the months since, she noticed how much the meme and the fallout affected her: She feels more secluded, and in the beginning of the summer, she “didn’t really want to go out” or go to work.

“I hope it brings awareness to other schools,” Ms. Harmon said, adding: “Make the school a better place — safer for students.”

Sheelagh McNeill contributed research.