DNA on Discarded Cigarette Butt Reveals Killer of Vt. Teacher 52 Years Later

A discarded cigarette butt has helped authorities solve the 52-year-old cold case murder of Vermont school teacher Rita Curran.

"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 in a news conference on Tuesday.

Police officials said DeRoos, an upstairs neighbor of Curran's, killed the 24-year-old after leaving his own apartment following a fight with his wife on July 19, 1971.

A cigarette butt found near Curran's body was submitted for DNA processing in 2014, but no genetic matches were found after a search through the country's law enforcement repositories, according to NBC News.

The police force worked with Virginia-based Parabon NanoLabs to search publicly available databases for the killer's identity, Trieb said, and that's when DeRoos was determined to be a potential suspect.

In 2019, investigators re-interviewed Michelle, the woman who was married to DeRoos at the time, and she revealed to them that her then-husband left their apartment for a brief period of time after they had a fight.

According to police, at the time of the murder, the couple had given police the alibi that they were home when Curran was killed. One of Curran's roommates who was not home, arrived at the apartment to find the woman was dead and that she had been strangled, per ABC News.

DeRoos later divorced his wife and after moving to Thailand where he became a Buddhist monk. He later returned to the U.S. and died of a drug overdose in 1989 in San Francisco, according to NBC News.

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A brother of Curran's said he does not think about her killer but that his thoughts are about what his sister and their parents went through, telling reporters: "I pray to my parents, and I pray to Rita."

"The random violence of her murder left a stain on our community, and it devastated her family," Jon Murad, acting chief of the Burlington Police Department said. "For 50 years they have waited for justice."