Columbia University students dumped dozens of mattresses outside the university president's home yesterday in protest over the treatment of Emma Sulkowicz, a senior who has pledged to carry a mattress around with her until her alleged rapist is expelled.

The protest involved over 150 members of the Columbia University community, including students, faculty members and alumni, according to the Columbia Spectator. Student activist group No Red Tape organizing the dump, which was inspired by Sulkowicz's "Carry That Weight" senior thesis. Sulkowicz alleges that she was brutally beaten and raped on the first day of her sophomore year, and says her rapist was found "not responsible." She and two other women who were allegedly raped by the same assailant say they were treated reprehensibly by the school administration and by the NYPD, and she, along with 22 other students, have filed three federal lawsuits against the school alleging that they've mishandled reports of sexual assault and rape.

Yesterday's protest was one of thousands held on campuses all over the country, as part of a “Carry That Weight” national day of action in Sulkowicz's honor. Barnard and Columbia students dumped 28 mattresses outside President Lee Bollinger's home:

Stacking mattresses on President Bollinger's doorstep. #carrythatweight

A photo posted by Jo Chiang (@jochiang) on

Carry That Weight #protest

A photo posted by Dylan C. (@dylpickledude) on

Protestors also left Bollinger a list of demands regarding the administration's handling of victims of sexual violence. The university has pledged to change its policies regarding sexual assault, but some students say that's not enough. "There is a simple solution to making this campus safe: Expel rapists," one protestor told DNAinfo.

Columbia students held a similar rally in September, bringing their own mattresses to an on-campus demonstration. Columbia students—and students on campuses nationwide—have won support from elected officials, and President Obama recently launched a nationwide campaign to combat sexual assault on campus.

The university tells us that "the people and policies dedicated to addressing gender-based misconduct at Columbia are unsurpassed among the nation’s colleges and universities," and that officials have made changes to the administration's handling of sexual assault. Their statement:

We understand that reports about these cases in the media can be deeply distressing and our hearts go out to any students who feel they have been mistreated. Importantly, the University will not address reports about individual cases or experiences. This is so not only because of federal student privacy law but also—and most fundamentally—because of our commitment to help students feel as comfortable as possible accessing the many resources to support them on campus without concern that the University would ever comment publicly on them or their experiences. As a University we have made substantial new investments to further strengthen our personnel, physical resources, and policies dedicated to preventing and responding to gender based-misconduct.