A NEW YORK DENTIST VOWS TO "48 HOURS" THAT HE DIDN'T KILL HIS LOVER'S HUSBAND - SO WHY DID HE END UP IN PRISON?

"Death and the Dentist" - Saturday, April 8

Gilberto Nunez, a former dentist in Kingston, N.Y., tells 48 HOURS correspondent Richard Schlesinger he didn't kill his best friend, who happened to be the husband of his lover, in an updated edition of "Death and the Dentist," to be broadcast April 8 (10:00 PM) on the CBS Television Network. But that's not why he ended up prison.

In his only television interview, Nunez talks about the love triangle at the heart of the murder case against him that thrust him into headlines and exposed a twisted tale of deceit that led to his downfall. "I'm innocent," Nunez tells Schlesinger. "I haven't done anything wrong."

Thomas Kolman was found dead by his wife, Linda, in his car outside of a gym in Kingston, N.Y. in 2011. The autopsy reported Kolman had an enlarged heart, but the medical examiner also found an unusual drug in his system - midazolam - a sedative sometimes used by those in the dental profession. The amount of midazolam found in Kolman would not normally kill somebody. But, because there was no explanation for why the drug would be there, the medical examiner called the death a homicide - acute midazolam poisoning.

Grainy surveillance footage of a car pulling up to Kolman's near the time of his death led police to Nunez. Police believe Nunez met Kolman in the parking lot and gave him the drug in a cup of coffee. Nunez denied being there. But in the investigation, Nunez admitted having an affair with Kolman's wife, and told police Kolman was fine with it. Nunez also had a penchant for impersonating other people in text messages and email, including his mother. Even the name of the CIA got dragged into the case through a fake ID.

"I did a lot of stupid things in the relationship," Nunez says, adding, "That doesn't make me a murderer."

It took four years for prosecutors to charge Nunez with second-degree murder and forgery. Prosecutors maintained Nunez was obsessed with Linda Kolman and did whatever he could to drive the couple apart. When that didn't work, prosecutors say he took the next step. But at trial, Nunez's top New York City defense attorney Gerald Shargel, who has represented such clients as Mafia boss John Gotti and actress Amanda Bynes, presented a very different scenario, saying Tom Kolman died of natural causes, insisting this is a murder case without a murder.

He was acquitted on the second-degree murder charge, but Nunez's legal problems were far from over.

48 HOURS: "Death and The Dentist" is produced by Ruth Chenetz and Dena Goldstein. Mead Stone is the producer-editor. Doreen Schechter, Joan Adelman, George Baluzy and Richard Barber are the editors. Patti Aronofsky is the senior producer. Susan Zirinsky is the senior executive producer.

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