Prosecutors argued that Mr. Naquin targeted Mr. Gruver for especially harsh treatment because he did not want him to join the fraternity, while Mr. Naquin’s lawyer argued that the pledge continued to drink of his own accord after the hazing event had ended.

Mr. Moore said there was “absolutely no winner in this case.”

“It is difficult for the defendant’s family and it is difficult for the victim’s family,” he said. “We have never alleged that the defendant wanted him dead or wanted to kill him, but his actions led to this young man’s death.”

Mr. Naquin was one of 10 students arrested after Mr. Gruver died, but he was the only one charged with negligent homicide. He was expelled from L.S.U. in the month after the death.

Three students were charged with hazing, a misdemeanor, the prosecutor said, adding that two had pleaded no contest and would be sentenced on July 26. The third has not yet entered a plea.

Mr. McLindon said his client was considering an appeal.

“It was a hazing event, but there were probably 10 other active members up there that night and at least five of them were handing out alcohol,” he said in an interview. “Matthew didn’t do anything differently from those boys, but he got picked out because he is very loud.”

“He has a very loud voice and everyone agreed he was the loudest one there,” Mr. McLindon said. “Unfortunately the jurors equated being loud to somehow being a leader and making that jump to criminal negligence.”

L.S.U. was shocked by the death in 2017 and suspended all Greek life activities on campus for several weeks that fall. It also revoked the on-campus registration of Phi Delta Theta until 2033 and convened a task force to study Greek life on campus.