DENVER (CBS4) – The federal judge presiding over the murder case against Harold Henthorn termed the 1995 death of Henthorn’s first wife, Lynn, “pretty bizarre,” during court proceedings in Denver Tuesday morning.

The comments from Judge R. Brooke Jackson came near the end of a two-day hearing to determine if a jury should be able to hear about the unusual death of Harold Henthorn’s first wife when he goes on trial in September for the death of his second wife, Toni.

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Henthorn faces a federal murder charge in connection with Toni Henthorn’s death in September 2012. She fell 140 feet from a rocky knob in Rocky Mountain National Park during an anniversary hike with her husband.

Harold Henthorn termed it an accident but federal authorities believe it was a premeditated shove that led to Toni Henthorn’s death and they have charged Henthorn with murder. He has pleaded not guilty.

Harold and Sandra Lynn (courtesy to CBS)

Harold and Sandra Lynn (courtesy to CBS)

When he stands trial later this year, prosecutors want jurors to also hear about the 1995 death of Henthorn’s first wife, Lynn. She died on a remote Douglas County road, late at night when the couple stopped to change a soft tire on their Jeep. According to Henthorn, Lynn dropped a lugnut or flashlight under the car and when she dove under the car to retrieve it, a jack failed and she was crushed. She was pronounced dead the next day.

After a six day investigation, the Douglas County Sheriff’s department pronounced it an accident and the coroner concurred. However following the death of Toni Henthorn in 2012, the Lynn Henthorn case was reopened by Douglas County and an active investigation is ongoing.

Prosecutors are also trying to persuade the judge to allow the jury to hear about a 2011 incident involving Toni Henthorn in which Harold says he accidentally dropped a beam on his wife’s head at their mountain cabin. She was seriously injured and prosecutors now believe the 2011 incident was Harold Henthorn’s first attempt to kill his second wife and want the jury to hear about that as well.

Harold and Toni Henthorn (credit CBS)

Harold and Toni Henthorn (credit CBS)

“The similarities in this case are really legion,” said federal prosecutor Bishop Grewell, during Tuesday’s court session.

Grewell said that in the deaths of both of his wives, Harold Henthorn created risky situations, insured he was the only witness, had significant life insurance policies on both of his wives and chose locations that were remote, insuring that it would take emergency medical personnel a long time to reach both of his wives.

Grewell said Henthorn set up scenarios that were “designed to delay emergency response.”

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Grewell said both wives deaths were “eerily similar events.” He portrayed Henthorn as a methodical, plotting serial wife killer.

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Jackson pressed Grewell on why Douglas County Sheriff’s investigators declared Lynn Henthorn’s 1995 death an accident if prosecutors were now concluding it was a murder case.

“Your theory is they (Douglas County Sheriffs investigators) were just incompetent?” asked Jackson.

Harold Henthorn and Sandra Lynn (courtesy to CBS)

Harold Henthorn and Sandra Lynn (courtesy to CBS)

Harold Henthorn’s attorney, Craig Truman, argued against the jury hearing about the Lynn Rishell death saying the case was 20 years old and witnesses memories have faded. Truman said some witnesses recollections were “very spotty.”

He pointed out the initial Douglas County ruling that the case was an accident and said even after the case has been reopened for two and a half years, no charges have been filed against Harold Henthorn.

“This was an accidental death,” proclaimed Truman and he called the initial 1995 sheriff’s investigation “pretty darn good.”

Jackson took the matter under advisement and is expected to issue a written ruling on what he will, or will not, allow to be admitted during the September murder trial.

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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.