William J. Brennan, an attorney for one of the fraternity members: "I spent the summer successfully defending my client against charges that should never have been brought in the first place".
New charges were brought on Monday against 12 defendants who previously had not been charged, and additional counts were brought against five who already were facing charges.
Centre County Judge Allen Sinclair dismissed all involuntary manslaughter and aggravated assault charges for the 18 Beta Theta Pi members charged in the case in September.
The charges come after a video police say was initially erased by a member of the fraternity while officers were inside their house was recovered.
"In fact, on video, Tim Piazza does not obtain his own alcohol at any point - rather, every drink consumed was provided to him by a fraternity brother", she said in the news release.
Prosecutors previously had video from elsewhere in the house, but not the basement. The 12th person, who is accused of deleting the video, was charged with tampering with evidence, obstructing administration of law and hindering apprehension.
The deleted video was recovered with the help of the Federal Bureau of Investigation, Parks Miller's office said. "It was manually deleted from certain menus".
"It's time to man up fellas", Piazza's dad, James Piazza, said Monday.
She referenced evidence from a previous hearing at which Becker and another person talked about deleting the video.
Deleted surveillance video leads to news charges filed in the Timothy Piazza manslaughter case.
The affidavit was not available later Monday.
"Over the last several months we listened to defense arguments centered around victim blaming", Jim Piazza said at the end of a press conference in Bellefonte announcing the new charges.
He called on those allegedly involved to take responsibility.
Any fraternity member seen on video serving alcohol to underage pledges were charged with hazing, furnishing to minor and unlawful acts relative to liquor, Parks Miller said.
Piazza died after he fell during an alcohol-fueled party, about 12 hours before a fraternity member called 911 to report Piazza's injuries, according to court documents. The most serious charges - involuntary manslaughter and aggravated assault - were also dropped for eight former fraternity members.