Last Updated Aug 10, 2017 7:59 PM EDT
BELLEFONTE, Pa. -- Additional video shot inside a Penn State fraternity house and played in court on Thursday showed a pledge stumbling and unsteady about three hours before.
The four-minute excerpt was played by prosecutors to illustrate. A shirtless Piazza was able to walk to close a door but had trouble keeping his pants up and then collapsed into a large chair in the Beta Theta Pi house's great room.
Members of the fraternity, since banned by the university, later realized Piazza was missing and found him in the basement,. The lead detective testified Thursday that he now suspects the basement video was purposely erased, and charges may result.
Piazza's friends waited some 40 minutes that morning to call for help, and medical experts have said the 19-year-old from Lebanon, New Jersey, had suffered severe head and abdominal injuries. He died the next day.
The preliminary hearing, now in its fourth day, will determine if there is sufficient evidence to send the case to county court for trial. The defendants are.
The charges for some include involuntary manslaughter and aggravated assault. Others face less serious charges that include evidence tampering, hazing, reckless endangerment and alcohol offenses. A fifth day of the hearing has been scheduled for Friday.
Piazza fell several times during a night of drinking that followed his participation in a pledge acceptance ceremony. Security camera footage inside the house recorded the response of fraternity leaders and other members as they dealt with the injured and intoxicated student with a series of ineffectual and even counterproductive efforts.
Excerpts from the footage, narrated by the lead detective during a previous court session, showed fraternity members holding down Piazza, strapping him to a loaded backpack to keep him from turning over and choking, pouring liquids on him and trying to get him to stand so they could dress him, even though he appeared to be unconscious.
Piazza was left on a first-floor couch overnight, in palpable agony. He made several clumsy attempts to get up but fell repeatedly and in some cases landed on his head.
Defense attorneys have challenged State College police Detective Dave Scicchitano about his investigation, zeroing in on what the video shows about their particular clients and asking him about how much hazing pressure Piazza would have felt.
On Thursday, the lawyer for defendant Luke Visser asked Scicchitano if he has looked into reports that two members of a visiting sorority may have been at the top of the basement stairs at the time of Piazza's initial fall. Scicchitano said he had and he urged the women to come forward.
"I would like to go after them if I knew where to look," Scicchitano said. "They're not wearing name badges."
Testy and sometimes bitter exchanges between Visser defense attorney Ted Simon and Centre County District Attorney Stacy Parks Miller caused District Judge Allen Sinclair to admonish them about "their back and forth - who's lying and who's not lying."
The fraternity itself also faces criminal charges, including involuntary manslaughter and aggravated assault. Two other defendants have waived the hearing.