IN HIS ONLY TELEVISION INTERVIEW, A NEW YORK DENTIST VOWS THAT HE DIDN'T KILL HIS LOVER'S HUSBAND, ON "48 HOURS," SATURDAY, SEPT. 17

Gilberto Nunez, a prominent dentist in Kingston, NY, tells 48 HOURS correspondent Richard Schlesinger he didn't kill his best friend, who happened to be the husband of his lover, in "Death and the Dentist," to be broadcast Saturday, Sept. 17 (10:00 PM, ET/PT) on the CBS Television Network.

In his only television interview, Nunez talks openly about the love triangle at the heart of a murder case that thrust him into headlines and exposed a twisted tale of deceit, family secrets and more.

"I'm an 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, NY, in 2011. Police didn't suspect murder at first. The autopsy reported Kolman had an enlarged heart, but the medical examiner also found an unusual drug in Tom's system - midazolam - a sedative sometimes used by those in the dental profession. The amount of midazolam found in him 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.

Police pulled surveillance footage from the area where Kolman's body was found. On the grainy footage, police spotted what they say is a white SUV next to Kolman's in the parking lot. Police say the only person they knew connected to Tom Kolman who had a white SUV was Nunez. Police believe Nunez met Kolman in the parking lot and gave him the drug in a cup of coffee. But Nunez denies being there. There are numerous texts between Tom and Nunez that illustrate the strong friendship.

The investigation into Kolman's death turned up several unusual twists. For starters, Nunez confessed to having an affair with Tom Kolman's wife, and he told police that Kolman not only knew about it, but he was also fine with it. And then there was Nunez's 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 tells Schlesinger, adding, "That doesn't make me a murderer."

Talking with Schlesinger, Nunez gets emotional. "Because Tom was my best friend, truly," Nunez says. "He was like a brother to me."

Nunez told police and Schlesinger that he didn't use midazolam in his practice. And since everyone knew about the affair, he said he had no reason to want his best friend dead.

It took four years for prosecutors to charge Nunez with second-degree murder and forgery. Prosecutors maintain 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 attorneys presented a very different scenario, saying Tom Kolman died of natural causes, insisting this is a murder case without a murder.

48 HOURS: "Death and The Dentist" is produced by Ruth Chenetz. Dena Goldstein is the field producer. Patti Aronofsky is the senior producer. Susan Zirinsky is the senior executive producer.

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