Transcript for Hearing set in Penn State fraternity-hazing death

that came there. Heading to a big day in court. More than dozens members of a banned Penn state fraternity in the death of Timothy piazza. The hearing will decide if there is enough evidence to go to trial and Eva pilgrim joins us with what details are expected to be made public. All eyes will be on the key piece of evidence, surveillance video, video prosecutors say shows exactly what happened the night a Penn state student died. For the first time video recorded inside a Penn state frat house the night a pledge died will be played publicly in court. We expect that videotape to be horrible, that it will be the kind of evidence which will make a significant impact. Reporter: 19-year-old Tim piazza died after falling head first down the stairs of the beta theta pi fraternity house this past February after a pledge party allegedly turned into an alcohol-fueled hazing ritual. The fraternity brothers accused of waiting nearly 12 hours before calling for help. We have a friend who is unconscious. He's -- hasn't moved. Probably going to need an ambulance. Reporter: 18 members of the banned fraternity are due in court. Eight facing charges of involuntary manslaughter and assault. A judge deciding if there is enough evidence for the case to go to trial. Prosecutors plan to play surveillance video of the incident, hours of footage. What we have here is evidence which is quite unusual and we're not in this case talking about who said something happened but rather what was recorded as to what happened. Reporter: Prosecutors allege his fraternity brothers tried to cover up their drinking and coordinate a story. One of the members not charged, telling our robin Roberts he tried to get piazza help. I said we should call 911. Get him in an ambulance, I got thrown against the wall. I didn't know what to do after that. I felt kind of useless. It's nice that he had good intentions at the time. But I don't know why anybody didn't pick up a phone. Reporter: And one of the defense attorneys agreeing this was a tragedy but saying it doesn't mean there was any intent involved. Since piazza's death Penn state has permanently banned beta theta pi and added new restrictions for all Greek organizations. I sat down with the piazza family. They are on a mission to change the way cultures operate especially Greek cultures on campuses across the country. They're not sure whether they're willing to watch that tape. Incredibly painful for them. Eva, thanks very much. Really appreciate it.

This transcript has been automatically generated and may not be 100% accurate.