DENVER (CBS4) – The second week of the murder trial of Highlands Ranch man Harold Henthorn saw a series of prosecution witnesses testify about the unusual death of his first wife in 1995, with one witness saying it was “one of the creepiest things I’ve come across in my life.”

Henthorn is on trial in federal court with prosecutors charging him with murdering his second wife, Dr. Toni Henthorn, by pushing her off a cliff in Rocky Mountain National Park during an anniversary weekend hike in 2012. Harold Henthorn has always maintained what happened to his 50-year-old wife was an accident.

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However, as part of that case prosecutors are being allowed to tell jurors about the May 1995 death of Henthorn’s first wife, Lynn. She died when the couple’s Jeep fell on her during a tire change on a remote Douglas County road. The Douglas County sheriff and the coroner’s office ruled within a week Lynn Henthorn’s death was an accident, but the sheriff’s department reopened that 1995 case in 2013 after learning of the death of Henthorn’s second wife.

Federal prosecutors maintain Henthorn intentionally killed his first wife for more than $600,000 in life insurance proceeds, the same motive they cite in the death of his second wife who was insured for more than $4.5 million.

On Monday, Patricia Montoya, a witness who came upon the Henthorn tire changing scene in 1995, testified when she and a carload of family members arrived after the Jeep had slipped off a jack and fallen on Lynn Henthorn, “He was a little frantic.” Montoya told the jury that when Montoya family members went to pull Lynn Henthorn out from under the Jeep, “He was very angry. We didn’t understand why.” She said Harold Henthorn yelled and screamed, “Don’t touch her … leave her alone.”

Harold Henthorn with his first wife, Lynn (left) and his second wife Toni (credit: CBS)

Harold Henthorn with his first wife, Lynn (left) and his second wife Toni (credit: CBS)

Montoya testified that it was puzzling since he had flagged them down for assistance. She said Harold Henthorn was “not wanting to help at all” and Montoya called the episode “very suspicious. I had nightmares about the lady. It was creepy … they were married but he wouldn’t do anything to help her. One of the creepiest things I’ve come across in my life.”

Within days Montoya visited the Douglas County Sheriff’s Office and asked if they had arrested Henthorn. She said despite that outcry detectives never interviewed her until 2013 and 2014. CBS4 had previously interviewed Montoya and aired her account of what happened that night.

Earlier that evening, a good Samaritan who lived in the area, Dwight DeVries, came across Henthorn and his wife before the attempted tire change took place. DeVries testified he stopped to offer help with the tire change. But he said Henthorn brusquely rebuffed his offers of assistance.

“It just really felt strange,” said DeVries. “He didn’t want my assistance whatsoever.”

VIDEO: Watch the CBS4 special “Inside The Investigation: Harold Henthorn

Devries said the Douglas County Sheriff’s Office had a short conversation with him about what he witnessed but they never actually interviewed him until about a year ago, after they reopened their 20-year-old case.

Also testifying about the 1995 case was Roxanne Burns, a former volunteer firefighter who was on the scene the night the Jeep fell on Lynn Henthorn. She talked to Harold Henthorn who she said “wasn’t very upset. He didn’t seem that upset to me. He said that she was changing a tire. The whole thing didn’t make sense to me,” recounted Burns.

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“He told me he did not know how to change a tire … odd,” said Burns.

Harold and Toni Henthorn (credit CBS)

Harold and Toni Henthorn (credit CBS)

Like the other witnesses, Burns said Douglas County investigators never interviewed her after the 1995 death, only approaching her in 2013 after the case had been reopened.

Earlier in the day a close friend of Harold Henthorn’s, Dennis Dahl, testified that he always believed Henthorn was an independent fundraiser for charities and nonprofits — a story Harold Henthorn told repeatedly. But after Toni Henthorn’s 2012 death, Dahl said Henthorn admitted “the story … was untrue,” that Harold Henthorn was unemployed.

“He said it was Toni’s idea,” testified Dahl, explaining that the ruse about Henthorn having a business in Colorado was necessary to make Toni Henthorn’s move to Colorado from Mississippi palatable for her family.

Dahl also testified about Toni Henthorn’s diamond wedding ring which has become a frequent topic in the trial. When she fell more than 130 feet to her death, her expensive diamond was missing from its setting. Dahl said Henthorn indicated investigators believed he had pried it out of the setting after the deadly fall.

“He said it was a horrible accusation,” remembered Dahl.

Sandra Lynn Henthorn (credit: CBS)

Sandra Lynn Henthorn (credit: CBS)

Dahl said Henthorn said he had “half a mind” to return to Rocky Mountain National Park to find it himself. He also said Henthorn suggested it might be nice if friends would go to RMNP to look for the missing diamond. Dahl said he did not make such a trip. However in a pretrial notice, prosecutors have indicated they have evidence the diamond was eventually found, although it has not yet emerged where the diamond was recovered.

Toni Henthorn’s mother, Yvonne Bertolet, testified Monday afternoon that Harold Henthorn referred to the park ranger investigating Toni Henthorn’s fall as “Barney Fife” who mostly puts out fires and hands out parking tickets. Bertolet testified that her family specifically asked Henthorn not to have his wife cremated, but he did anyway saying it was “Toni’s wishes.”

Prosecutors believe the cremation was an attempt by Henthorn to conceal evidence in the case. Bertolet testified that when her family put on a memorial service for Toni about three weeks after her death, Henthorn said “I just want to get on with my life.” Bertolet said he appeared “almost like, ‘Let’s get this over.'”

Testimony from prosecution witnesses will continue Tuesday and federal prosecutors say they expect to have called all their witnesses by the end of the week.

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CBS4 Investigator Brian Maass has been with the station more than 30 years uncovering waste, fraud and corruption. Follow him on Twitter @Briancbs4.