The 19-year-old died of an accidental overdose after he ingested counterfeit Percocet pills containing fentanyl.
This year marked the second grim anniversary of his death. Weiner was found dead inside the Theta Delta Chi (TDX) fraternity house where he lived, located on-campus.
"On January 15th, Eitan showed clear signs of an opioid overdose. The on-call RA called 911," Weiner's sister Ya'el told ABC7 News. "And there was no follow-up in the 36-hours leading up to his death on January 17th."
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His family filed in December. Court documents name the university, the now inactive fraternity, and several others.
According to Weiner's sister, the lawsuit is a "last resort" for the family. California's statute of limitations to bring a wrongful death action is two years.
"We knew that they were going to get to the point that they weren't going to be compelled by any means to do anything," Ya'el Weiner explained. "And this was our last option."
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The lawsuit was a difficult decision for the family, considering the Weiner's have dedicated nearly three decades to Stanford. Both parents are long-time employees and Ya'el is a 2019 graduate.
"My mom has worked at the law school and now the medical school," Weiner said. "She's Vice President of Development and my dad's a professor of history."
The family's attorney, Carlos Gonzalez told ABC7 News, "The challenge is the emotional toll that it takes to see an institution that you have invested so much time in, turn its back on you."
The lawsuit alleges the university failed to follow its own policies to protect students, that the school ignored local warnings about counterfeit Percocet pills, and more.
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Stanford University published a response to the lawsuit on Thursday. The school also addressed it's commitment, it's response and what it's doing to combat drug and alcohol misuse.
On Friday, ABC7 News received a similar response from Stanford's University Communications team which said in-part:
"We were saddened to receive news of this lawsuit as our community continues to mourn Eitan's tragic death, and we have great sympathy for his family and those affected by it. We do not agree with many of the allegations in the complaint and we will defend the university against this lawsuit."
"It doesn't change the fact that they need to own up to what has already happened," Ya'el said. "That they're saddened by this lawsuit, because they're mourning, it's an insult. It's a poke in our eyes and salt in our wounds."
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"If everyone had just done what they were supposed to do, Eitan would still be with us today," Gonzalez shared.
He added, "It failed to follow its own policies. It failed to do what was right. It could be any named institution to us, it does not matter. What hurts is that this is a Stanford family."
"We've tried to work with Stanford. We begged and pleaded for them to step up and do the right thing- hold themselves and their students, and their student organizations accountable," Ya'el Weiner told ABC7 News. "But they failed to do that. And they've just been resistant to cooperating and doing so. And so, this is just finally the opportunity for us to seek some sort of justice and some measure of accountability."
The lawsuit also named a childhood friend who Weiner's family said sold the drugs. Three additional people were named, identified by the family as Weiner's roommates at the time of his death.
"They compromised a criminal investigation, they concealed evidence, and they have gone on to live their lives with no accountability," Ya'el Weiner told ABC7 News. "They're about to graduate with their Stanford degrees, Eitan doesn't get to graduate in the spring."