BELLEFONTE, Pa. — Fourteen members of a disbanded Penn State fraternity must stand trial in the hazing death of a pledge, but a judge on Friday tossed out the most serious charges, including involuntary manslaughter and aggravated assault.

Eight of the former Beta Theta Pi brothers saw those serious charges dismissed. In addition, four of the total 18 defendants charged with only single counts were dropped entirely from the case.

The parents of Timothy Piazza, the 19-year-old who died following a party at the Beta house in February, said they were disappointed about the judge’s decision, but are looking to the trial for justice.

“There needs to be a deterrent because we lost our son,” mother Evelyn Piazza told NBC News.

She added that if the defendants “acted like a brother or a friend or a responsible human being, it would have been a lot different. We wouldn’t be here.”

 Judge to rule on whether Tim Piazza fraternity hazing case can go forward 0:39

The charges that still remain against some of the former fraternity brothers are misdemeanors, including a reckless endangerment charge, which carries up to a two-year prison sentence, as well as hazing and alcohol-related charges.

Some originally faced aggravated assault counts, a first-degree felony, and could have seen as many as 10 to 20 years in prison if found guilty.

“This court has dismissed those charges and has done it in a resounding way,” defense attorney Theodore Simon, whose client, Luke Visser, had been facing a felony charge, told reporters.

After the judge’s ruling, District Attorney Stacy Parks Miller announced that she plans to refile charges and denied there was prosecutorial overreach because the more serious charges were dropped.

“We obviously believe in the original charges or we wouldn’t have brought them,” Miller said.

She added that the Piazzas are “devastated” and “we have to go through this terrible process again.”

It was not immediately clear if the students will be tried together, but District Judge Allen Sinclair said he wouldn’t expect the trials to begin until at least the spring.

Two other fraternity members had earlier waived their right to a preliminary hearing, but must still have their cases heard before a jury.

The defendants have denied all charges.