The preliminary hearing, which enters its fifth day on Friday, is to determine whether prosecutors have enough evidence to support the charges made against 16 of the defendants. The investigation isn't finished and more charges could be coming related to the missing videotaped moments, reports CBS News correspondent Anna Werner.
Centre County District Attorney Stacy Parks Miller suspects someone tampered with the basement surveillance cameras at the Beta Theta Pi house to get rid of evidence.
"That is the belief where we're headed in this investigation. We will not say who it would be or that we're willing to file charges until we have a forensic report back," Miller said.
On the stand, Scicchitano did not identify a suspect.
Piazza died in February following an initiation ceremony that involved heavy drinking. Security footage showed him stumbling and hitting his head repeatedly. He was found the following morning in the basement.
"What was the stunning revelation today is that there actually was a videotape in the basement which was likely erased and if that tape was erased, then this coverup is even larger than we ever even anticipated or expected or known about," said Tom Kline, the Piazza's family attorney.
Eighteen members of the now shuttered Beta Theta Pi fraternity have been charged. Ten face misdemeanors like hazing, furnishing alcohol to minors, or reckless endangerment. Two of the 10 waived their right to the preliminary hearing. The others face additional charges of involuntary manslaughter and aggravated assault.
Leonard Ambrose represents Joseph Sala, one of the eight defendants charged with the most severe crimes. He says prosecutors overcharged his client.
"Well, the appropriate charge really for everybody would be underage consumption of alcohol. I mean, that was it," Ambrose said.
The question is whether video from the basement might show not only Piazza's fall down the stairs, but also that heavy drinking earlier in the evening.
The prosecutor says she has asked the FBI to try to recover the destroyed footage, but has not heard back yet as to whether they have had any success.
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