CENTREVILLE, Mich. (WOOD) — Now that the recently charged suspect in the 1988 death of Cathy Swartz has died in jail by suicide, investigators fear questions in the case will never get answered.

Robert Waters, 53, died on Saturday at the Beaufort, S.C., County Detention Center just days before Michigan police were planning to pick him up.

St. Joseph County Prosecutor David Marvin said he was looking forward to a trial.

“I wasn’t concerned about proving what happened, but I wanted to know why it happened, and I’m afraid we may never know,” Marvin said on Monday.

Waters, who once lived near Three Rivers, was charged with open murder in the Dec. 2, 1988, death of 19-year-old Cathy Swartz in her Three Rivers apartment. The killer had beaten her, strangled her and slit her throat. He’d also written, “I was here,” in her blood at the scene.

Waters, a plumber living in South Carolina, was arrested on April 30 after DNA geneology tests led police to his family.

Police said his fingerprint matched a print left in blood on the victim’s phone.

He was a childhood friend of Cathy’s fiance, Mike Warner, who discovered the body.

Cathy’s baby girl, Courteney, was in another room. Her grandparents raised her. She’s 35 now.

“She was just a little kid and it’s impacted her entire life,” Marvin said. “I just wanted to give her an answer.”

Former prosecutor Jeff Middleton, who worked the case for years and is now a district judge, heard about the arrest from the current prosecutor.

“I was gratified and sad that those people who worked so hard on it never knew, and Cathy’s mom and Cathy’s dad. They never knew,” Middleton said.

Middleton said the current prosecutor texted him over the weekend about the suicide.

“I thought 35 years of guilt expresses itself in different ways and that’s apparently how this was resolved,” Middleton said.

Marvin, the current prosecutor, said he was out working in his yard when he heard the news.

“I was very, very upset,” he said. “I think that that guy owed a lot of us an explanation, especially Courteney, and to deprive people of that is cowardly, it really bothers me.”

He wants to know how Waters could move on with his life.

“Apparently there was no criminal history, and he lived a prosperous life, loved by his family, and he was respected in the community, and he apparently did well.”

Property records show he was living in a $500,000 home on a cul-de-sac in Beaufort County. He and his wife operated a plumbing company that had gotten five-star reviews online.

In a press release, Beaufort County officials said guards found Waters unresponsive in his cell on Saturday during a routine check. They tried to revive him, but he was pronounced dead at the scene. They said officials determined the death was a suicide, though they didn’t say how he died or whether he’d been on suicide watch. The South Carolina Law Enforcement Division is investigating.

“I think by what happened, I think that he, one, admitted that he did it, and two, admitted that he’s a coward,” Marvin said.