DENVER (AP) – Attorneys for the man accused of shoving his second wife off a cliff in Rocky Mountain National Park want details of his first wife’s death barred from evidence during his trial.

In Monday filings in federal court, Harold Henthorn’s attorneys also asked a judge to keep prosecutors from discussing a situation in which his second wife, Toni Henthorn, was struck by a falling beam at their cabin.

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Henthorn is charged with first-degree murder in Toni Henthorn’s fall during a Sept. 29, 2012, hike. Prosecutors have said he could not explain to investigators why he had a park map with an “X” drawn at the spot where she fell.

Harold Henthorn and Toni Henthorn (credit: CBS)

Harold Henthorn and Toni Henthorn (credit: CBS)

They also say there are glaring similarities between her death and that of Henthorn’s first wife, who was crushed when a car slipped off a jack while she and her husband were changing a flat tire in May 1995. Henthorn was the only witness.

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Investigators have reopened the investigation into the death of Sandra Lynn Henthorn, which was initially ruled an accident. Henthorn’s attorneys said they have received no new information about the case, and it would be an unfair distraction if prosecutors were allowed to dwell on it.

Sandra Lynn Henthorn (credit: CBS)

Sandra Lynn Henthorn (credit: CBS)

“The prosecution wants to distract the jury with several multi-day trials within the trial, aimed at destroying Mr. Henthorn’s character,” attorneys Craig Truman and Joshua Maximon wrote in the filings. “If the prosecution is successful in speculating about the past by slandering his character, it follows that the prosecution will never have to prove its case.”

They also want to keep prosecutors from focusing on a situation in which Toni Henthorn was struck by a 20-foot beam while working at the couple’s mountain cabin. Henthorn was again the only witness, and prosecutors say it was an unsuccessful attempt to kill his wife. Henthorn’s attorneys say it was an accident.

A judge did not immediately rule on the requests, which could be discussed during court hearings in May.

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