It took nearly 52 years, but Vermont detectives stayed on this case until this week, when they announced they had solved the 1971 murder of 24-year-old school teacher Rita Curran in Burlington.

The culprit, Burlington Police said, was William DeRoos, who was 31 at the time of Curran’s murder and lived upstairs with his newlywed wife at the time, according to the Associated Press.

The key piece of evidence, they said, was DNA from a discarded cigarette butt found in Curran’s apartment

“We’re all confident that William DeRoos is responsible for the aggravated murder of Rita Curran, but because he died in a hotel room of a drug overdose he will not be held accountable for his actions, but this case will be closed,” Burlington Police Detective Lt. James Trieb, the commander of the Detective Services Bureau, said Tuesday during a news conference.

DeRoos and his wife had been married for just two weeks on July 19, 1971. The two had an argument, police said, and he left for “a cool down walk,” returning 70 minutes later. When he got back, he told his new wife not to tell anyone he’d been out. When detectives questioned them the next day — after Curran’s roommate came home and found her body — both DeRooses told them they’d been home all night and saw and heard nothing.

The two left Vermont shortly after Curran’s murder and divorced when DeRoos went to Thailand became a monk. DeRoos remarried when he came back to the United States, and died of drug overdose in 1986 in San Francisco.

More than 30 years after the murder, detectives sent the cigarette butt out for DNA testing, but the profile returned to them didn’t match anyone on file. Five years later, in 2019, detectives led by Trieb set out on a new look at the case, working it as if it had just happened.  They contracted a DNA company that compared samples with those on file in commercial DNA companies, and last August, the detectives were told that the sample pointed to DeRoos through members on both sides of his family.

One of the detectives, Thomas Chennette, tracked down DeRoos’s first wife, who by then lived in Oregon, and reinterviewed her. She told him she had lied in 1971 and that her husband had left the house, for more than an hour after a fight. Chennette said on Tuesday he didn’t think she knew he’d killed Curran and that she’d protected him because he had a criminal record.

“I think she lied at the time because she was young. She was naive. She was newly married. She was in love,” Chennette said.

Police said DeRoos entered Curran’s apartment through an unlocked door — her roommates were out to dinner, and she and DeRoos didn’t know one another. He beat her, sexually assaulted her, and strangled her, leaving her dead in her bedroom, WCAX reported.

“The cigarette dropped there and burned out on the floor next to her body,” Trieb said.

“We were numb,” Mary Curran Campbell, Rita’s sister, said. “Fifty-one-and-a-half years and it’s the guy upstairs.”

Curran’s parents died before detectives solved the case, but Curran Campbell and her brother were present at the news conference.

“I don’t think so much about the guy who did this as I do about Rita, my parents and what they went through,” Tom Curran said during the event. “I pray to Rita and I pray to my parents.”

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[Featured image: Rita Curran/handout]