Brown University has sanctioned two fraternities, saying they created an environment that "facilitated sexual misconduct" by failing to monitor parties and failing to properly safeguard the service of alcohol.
Phi Kappa Psi will loose recognition for four years, including the loss of its housing, effective immediately.
Sigma Chi has been sanctioned with probation until fall 2016. The fraternity cannot sponsor social events, or conduct recruitment, rush, or initiation processes.
The sanctions come after two students alleged they were served drinks laced with a date rape drug at a Phi Kappa Psi party in October. One of the students said she was sexually assaulted after the party.
In another October incident, Brown officials say a student reported non-consensual sexual contact at a party in the Sigma Chi basement. Brown says the student was unable to identify a specific person in connection with the incident.
No members of either fraternity have so far been charged with sexual assault or sexual misconduct, but Brown officials say they are being sanctioned because the parties were not registered.
"The measures we are taking this spring reflect our interest in preventing sexual assault by addressing the campus climate at Brown," wrote University Executive Vice President for Planning and Policy Russell Carey, and Margaret Klawunn, Vice President for Campus Life and Student Services. "All Brown community members need to be involved in preventing sexual violence, and all student organizations are expected to ensure that adequate security measures are in place to promote safe events and activities."