It happened at a fraternity where Brendan Young and Daniel Casey both served in leadership roles.
Authorities say Young and Casey pleaded guilty to 14 counts of hazing and a single count of reckless endangerment.
Young served as president of Beta Theta Pi fraternity and Casey was vice president and pledge master, according to police.
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The incident happened on February 2, 2017. Police say 14 pledges, including sophomore student Timothy Piazza, arrived at Beta Theta Pi for a pledge acceptance ceremony.
Pledges were then led to a basement and directed to drink from a vodka bottle. The pledges reportedly consumed a life-threatening amount of alcohol throughout the evening.
Piazza then reportedly fell down a flight of stairs after having consumed significant amounts of alcohol. In previous reports, experts estimated that the victim's blood-alcohol content was between 0.28 and 0.36 at the time.
Piazza fell repeatedly throughout the evening, according to reports. His fraternity brothers did not call the police until the next morning.
The 19-year-old from New Jersey died days later in the hospital.
Young, 28, and Casey, 27, participated in and facilitated the hazing event, according to investigators.
"There should be no discussion of this case without recognizing the tragic loss of life and resulting devastation for Mr. Piazza's family and friends," Attorney General Michelle Henry stated in a news release. "Mr. Piazza was simply seeking to join a social organization for the benefits of community and shared experiences, as so many university students do. Most of those students go on to successful lives and careers - basic expectations following college which Mr. Piazza never had the opportunity to experience."
Young and Casey's sentencing is scheduled for October 1.