CAN NEVER-BEFORE-SEEN EVIDENCE OBTAINED BY "48 HOURS" PROVE THERE WAS NO MURDER IN THE CASE AGAINST A NEW YORK WOMAN CHARGED WITH KILLING HER FIANCé DURING A KAYAKING TRIP?

"48 HOURS: Death on the Hudson"

Saturday, Sept. 12, 2015

Can never-before-seen evidence obtained by 48 HOURS prove there was no murder in the case against a New York woman charged with killing her fiancé during a kayaking trip? 48 HOURS will broadcast the new information in the case against Angelika Graswald, who has been charged with killing Vincent Viafore, in "Death on the Hudson" to be presented Saturday, Sept. 12 (10:00 PM, ET/PT) on the CBS Television Network.

"The police theory of this case is really outrageous," forensic scientist Mike Archer tells 48 HOURS Correspondent Peter Van Sant. Archer, who was retained by Graswald's legal team, says it is "perplexing" that Graswald has been charged with murder.

Graswald and Viafore set out on the Hudson River using kayaks on April 19, 2015. Along the way, as the weather changed, Viafore's kayak capsized. He wasn't wearing a life vest. The water was reportedly 46 degrees and choppy. Police say his kayak was missing a plug that allowed water to fill his narrow boat as they attempted to return home.

"I'm in the Hudson River, my fiancé fell in the water, can you please call anybody," Graswald told a 911 dispatcher in a recording of the call obtained by 48 HOURS. "I can't get to him. It is very windy and the waves are coming in and I can't paddle to him. He is getting further and further away from me... he's going to drown."

Viafore then disappeared under the water.

Ten days later, Graswald was questioned by police for approximately 11 hours and then arrested for murder in the second degree. Investigators maintain Graswald killed Viafore because she stood to gain $250,000 in insurance payouts and that their relationship had soured. Investigators also said she made conflicting statements and made statements that implicated her in the crime.

"It was a complete shock," Viafore's mother, Mary Ann tells 48 HOURS. "I was devastated that she would do that to my son, who was so good to her."

Her defense team argues Viafore's death was an accident, nothing more, and the plug in the kayak police say led to his drowning was removed long before the incident.

Viafore's body was recovered from the Hudson more than a month after he disappeared on May 24, 2015.

"I want to believe she didn't do it, but then again, the police know something I don't know," Viafore's friend, Sheri Parte tells 48 HOURS.

Was Viafore killed, or was his death a tragic boating accident? Van Sant and 48 HOURS investigate the case through interviews with legal, forensic and interrogation experts, friends of Graswald and Viafore, and an examination of key evidence in the case.

"Our investigation has uncovered evidence that may change people's perception of the case and bring into question whether a murder occurred," Van Sant says.

48 HOURS: "Death on the Hudson" is produced by Patti Aronofsky, Elena DiFiore and Lourdes Aguiar. Gregory McLaughlin is the producer editor. Ryan Smith and Kathleen O'Connell are the development producers. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.

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