A Norwalk lieutenant's work is being credited for the arrest of the suspect in a homicide case from 1986.

Lt. Art Weisgerber has been investigating the Kathleen Flynn homicide for the past 17 years. His work helped lead to the recent arrest of Marc Karun, who has been charged with special circumstances and kidnapping for the death of the 11-year-old girl in 1986.

Weisgerber was able to tie Karun to the crime using new DNA evidence, along with similarities to other sexual assaults with which Karun was charged.

Weisgerber comes from a law enforcement family - his father and grandfather were New York City police officers. He became part of the cold case unit in Norwalk in 2002, and says the Flynn case was one of the first he was given.

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Weisgerber went on to run the cold case unit from 2005 until 2018, even when he left the detective bureau and became head of the crime scene unit. Last year, he transferred most of the cold case responsibilities back to the detective bureau but kept a handful of cases he worked on for years, including the Flynn case.

Weisgerber has nine binders of information on the Flynn investigation and estimates he's read them 40 to 50 times.

"It's long-term work... you have to be like a fisherman because you're throwing in your bait and you're working on it, but you don't expect anything to happen right away," he says.

Weisgerber says another reason he enjoys investigating cold cases is the relationships he often builds with the victims' families over the years.

He says the cold cases he has are from the ‘70s and ‘80s, including the murder of Evelyn Colon in 1990 and the disappearance of April Grisanti in 1985.