The Adams County District Attorney's Office announced on June 30 that it had filed sexual assault charges against Ian Thomas Cleary, 28, of Saratoga, California. Authorities, however, have not yet found Cleary or released a photo of him.
Keeler was on vacation with her boyfriend last year when she says she saw what appeared to be multiple Facebook messages from Cleary. One specific message, she said, admitted to the attack.
"So, I raped you," Keeler said the message read in an interview with ABC News in May. "I'll never do it to anyone ever again."
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The charges were filed after what Keeler's lawyer, Laura Dunn, says was an outpouring of support following public appearances by Keeler on news platforms, including ABC News. Dunn said they then joined forces with the Pennsylvania Coalition Against Rape to further push for the charges to be filed.
"Shannon burst into tears," Dunn told ABC News on Wednesday about Keeler learning charges had been filed.
"She has been fighting for over seven years in this case to get charges -- to get an arrest warrant. ... So, for her, it was a big moment," Dunn said. "But as her attorney, my mind was onto the next: when is this arrest going to be effected? Where is Ian Cleary? We have concern that there was no arrest made yet in this case and we don't want to see him absconded from justice."
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Dunn said they believe Cleary is in Europe, "possibly France," or Australia. She asked for help from the public in finding him and turning him in.
Andrea Levy, legal director at the Pennsylvania Coalition Against Rape, says prosecution for these types of cases can be an uphill battle. She has had numerous clients who reported their sexual assault and were told "no" by prosecutors. She said that despite attempts to provide additional information to prosecutors as well as resources to support the county and push for action, most attempts are not successful.
"Ninety percent are denied," she said, referring to cases on which she has worked.
Keeler was a freshman at Gettysburg in 2013 when she attended the frat party with her friends to celebrate the end of the semester. She told ABC News in May that Cleary, who was at the party but not a member of the fraternity, began to bother her and at one point insisted that she dance with him. She said he also tried to kiss her.
Keeler said she felt uncomfortable and asked a male friend to walk her back to her dorm room. Cleary confronted them during the walk back and offered her friend $20, she said.
"He said to my friend, 'Let me have her. Please let me have her,'" Keeler told ABC News in May. "My friend pretty much told him, 'I'm just trying to get her away from you.'"
Keeler said she was getting ready for bed in her dorm room when she heard someone knocking on the door and opened it thinking a friend had visited. Instead, it was Cleary, she said, who refused to leave and eventually assaulted her.
"He did force himself on me and raped me," Keeler said. "After he did that, he started crying."
She said he ran out of the room after apologizing. "I'm sorry. I didn't mean to hurt you," she said he told her, in part.
Keeler said that soon after, she reported the incident to campus and local police, who questioned her for hours and had her submit a rape kit. A Gettysburg College investigative report obtained by ABC News cites a written statement from Cleary from that time containing a general denial that he "engaged in any actionable misconduct."
Keeler said he dropped out of Gettysburg College during the next semester, thus ending the school's Title IX investigation.
"We applaud our former students' bravery in continuing to bring these issues to light," Gettysburg College said in a statement, adding, "We will continue to prioritize our efforts around sexual assault awareness. We know this work is ongoing and far from complete."
Despite her full cooperation with authorities, then-District Attorney Shawn Wagner declined to charge Cleary, saying he did not have enough evidence to prosecute. She said he told her, "When alcohol's involved, it's really difficult to prove that a sexual assault occurred."
Now a county judge, Wagner declined a request for comment from ABC News. Cleary also did not respond to requests for comment via email.
Former FBI agent and ABC News contributor Brad Garrett says the simplest way to track fugitives overseas is through the FBI, which has agents stationed in "virtually every country."
"The real key in a fugitive investigation is, it's extremely difficult to stay on the run, for starters," he said. "In other words, all of your credit cards, all of your banks, anything that's digital can track you. ... And so, it's because of all that, they ultimately do get caught."
Dunn said that Keeler hopes to learn more about Cleary's past, including whether there were other incidents like hers. "If that's the case, we may be looking for more significant time in the sentence related to this matter." But she said they're also concerned about his well-being and that they hope he can be rehabilitated.
Keeler told ABC News in May that she was scared people wouldn't believe her when she came out about her story all these years later, and that it would hurt her career and come to "define" her. Still, she said she hopes other people who hear about her story after going through something similar know that they're not alone.
"We, together, can help ... positively impact the broken system," she said.
If you or someone you know has experienced sexual assault, know that you are not alone. Help is available anytime. Call the National Sexual Assault Hotline at 1-800-656-4673.
ABC News' Alexandra Myers, Caroline Guthrie & Kendall Coughlin contributed to this report.