This Woman Has An Ingenious Plan To Stop Repeat Sexual Assault On College Campuses

Jessica Ladd says her new software, Callisto, could stop almost 60% of campus sexual assaults.

This Woman Has An Ingenious Plan To Stop Repeat Sexual Assault On College Campuses
Illustrations: Ozerina Anna via Shutterstock

As many as 1 in 4 women in college experience unwanted sexual contact–yet, as recent scandals have brought to light, instead of addressing these incidents, many schools instead swept the issue under the rug for years. New software, called Callisto, is simple yet–in theory–it could be incredibly effective at both deterring assault, making reporting easier, and catching repeat offenders.


Callisto, which is now being piloted at two colleges, was created by Jessica Ladd, a survivor who is also an infectious disease epidemiologist. Previously, through her nonprofit Sexual Health Innovations, she had invented a system to make it easier for people to notify sexual partners that they have an STD.

After talking to many survivors and reflecting on her own experience, Ladd realized that many women want to avoid the trauma of reporting their assault to the police or campus administrators, but if they don’t report, they are nagged by the guilt and self-doubt of wondering whether their assailant will victimize others.

The software allows students to create a securely encrypted and time-stamped record of their assault, documenting the circumstances of their attack in as much detail as they want from the comfort of their own dorm room or wherever they feel safe. From there, only if he or she chooses, the student can either send a report to the school. Or, she can decide not to report it right away but enter it into Callisto’s matching system.

The matching system is the most interesting innovation. It works by adapting the financial concept of escrow for use in a shockingly different domain. Escrow accounts are typically used in real estate transactions, class action lawsuits, and software licenses to ensure that different parties in an agreement follow through on their promises. In Callisto’s system–a kind of information escrow–the time-stamped record is held in the system and is released to the school at a later date only if a second student reports an attack by the same assailant. When they receive the report, the school knows there have already been two victims and can reach out to both.

“Knowing that you weren’t the only one changes everything,” says Ladd. “It changes the way you frame your own experience. It changes the way you think about your perpetrator. It means that if you do come forward, you’ll have someone else’s back and they’ll have yours.”

In STD prevention, the most cost-effective prevention approaches focus on the people who spread disease to many people. Ladd thinks stopping prolific attackers on campus could show similar dividends; she says 59% of sexual assaults could be prevented by catching these repeat offenders earlier on. This figure is based on an estimate that 90% of assaults are committed by repeat offenders, but reporting rates are so low that most get away with it. Campuses that widely and very publicly use Callisto could also prevent crimes, she believes, since perpetrators would know they have a high risk of getting caught: “We’re creating a real deterrent to assault for perhaps the first time.”


Pomona College and the University of San Francisco are the first two campuses to adopt Callisto this school year. For Pomona–which has faced its own major scandal and student protests last year for mishandling sexual assault cases–the initial roll-out involved customizing its Callisto site to make sure it was a source of information for students about all of Pomona’s policies and procedures. When the school year began last fall, the school launched a publicity campaign, including training sessions with student leaders, stickers, posters, and flyers.

So far, though it’s been going well, the school hasn’t received reports through the service, says Pomona’s associate dean and Title IX coordinator Daren Rikio Mooko. Ladd says that there has been a good amount of traffic to the site and that, overall at both schools, over 40% of the records that have been entered have also been entered into the matching system. “Defining success with Callisto is going to be kind of a moving target, or a really difficult target to pin down,” says Mooko.

The biggest initial impact could simply be in giving students another reporting option. “Say we have 100 survivors on campus, there’s probably 80 different preferences for how they report their assault,” Mooko says. “Prior to Callisto, we had one option for all of them–and that was to come and talk to an administrator.”

Ladd is working to launch Callisto at three to five new schools in the next school year. But she also sees a broader potential to use a similar concept in settings like the military and in workplaces.

From her own personal perspective, she says she’s always wondered whether her assailant ever acted again. She has spoken to him, and she doesn’t think so. “I’ll never really know,” she says. “My hope was that if I had a system like Callisto that would have enabled me to save the record, keep my options open, and only take action if this became more of a pattern–that would have really met my emotional needs as well as our societal needs to try to particularly stop repeat offenders.”

About the author

Jessica Leber is a staff editor and writer for Fast Company's Co.Exist. Previously, she was a business reporter for MIT’s Technology Review and an environmental reporter at ClimateWire.