Reading from the coroner's report, Scicchitano said the manner of Piazza's death was accidental and due to a fall, while the cause was "multiple traumatic injuries".
Prosecutors plan to play the surveillance video of the incident, which is hours of footage.
The Beta Theta Pi members and the fraternity itself face the preliminary hearing that will determine if there's enough evidence to send the case to trial.
Pledges, including Piazza, could be seen moving through various points in the house during the drinking "gauntlet", consuming vodka, beer and wine.
Piazza died February 4 at Hershey Medical Center after running the so-called "gauntlet" - a challenge in which pledges chug vodka, wine and beer - with doctors estimating his BAC had been close to.40 at the time of death.
Civil attorney Tom Kline, who represents Piazza's parents, called the tape painful to watch. Doctors say he suffered severe head and abdominal injuries.
"You can not watch it without the heaviest heart and tears in your eyes", Kline said.
Andy Shubin, an attorney for one of the defendants, said during a break in the hearing that it was "cruel and inhumane punishment" to make attorneys be in court for more than 10 hours, according to Piazza.
Now a judge will decide whether 18 members of Beta Theta Pi fraternity should face trial for a hazing ritual that turned fatal. "We hope to develop more information during the preliminary hearing process, and beyond, that will demonstrate that numerous charges in this case are just not applicable to the conduct". 8 members face charges of involuntary manslaughter and assault.
Some frat brothers try to restrain him at times throughout the evening and put a backpack on him to keep him upright so he wouldn't choke on his own vomit.
"To hit him and slap him and brutalize him, they should not have been trying to get a response", Piazza's brother, Mike, told CBS News.More news: Theresa May tries to quell public anger, meets fire victims
BELLEFONTE, Pa. (AP) Security camera footage of the night a Penn State pledge was fatally injured at a fraternity event is expected to be at the center of a court hearing.
Meanwhile, the party appeared to go on, as people came and went, some looking concerned about his condition while others seemed to take no notice.
By about 3 a.m., the detective said, Piazza was left alone on the couch.
Around 5 a.m., the cameras captured Piazza falling head-first into an iron railing.
"The videotape is terrible, and it is gruesome", said Piazza family attorney Tom Kline.
Nobody called 911 until about 12 hours after Piazza's first fall.
Authorities have said members of the fraternity resisted summoning help until well into the next morning.
Parks Miller said by showing the video - combined with testimony from Scicchitano - the state seeks to show fraternity members had prior knowledge of the dangers involved in an alcohol-fueled hazing and recklessness by doing it again.
As the fraternity brothers carried Penn State student Tim Piazza up the stairs, he was still alive, a police detective testified on Monday, but the 19-year-old "looked dead, he looked like a corpse". But they left before the video began airing on a small screen in the front of the courtroom.
Penn State has permanently banned the fraternity, saying the school found "a persistent pattern" of excess drinking, drug use and hazing.