DENVER (CBS4)– On the first day of jury selection for Harold Henthorn, the Highlands Ranch man charged with killing his second wife, Federal Judge R. Brooke Jackson told about fifty prospective jurors the upcoming trial “will be a doozy.”

Henthorn is set to go on trial next week for the 2012 death of his opthamologist wife, Dr. Toni Henthorn, who fell to her death in September 2012 during an anniversary hike with her husband.

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Harold and Toni Henthorn (courtesy to CBS)

Harold and Toni Henthorn (courtesy to CBS)

There were no other witnesses. Harold Henthorn has pleaded not guilty.

Prosecutors believe Henthorn pushed his wife off a cliff to her death. They also believe Henthorn killed his first wife, Lynn, who died in a freak accident in 1995. However, that case was ruled an accident by Douglas County authorities, although they now say they are taking a second look at the case in light of the charges against Henthorn in his second wife’s death.

Harold and Sandra Lynn (courtesy to CBS)

Harold and Sandra Lynn (courtesy to CBS)

Henthorn was never charged in connection with his first wife’s death.

About half the prospective jurors who were summoned on Wednesday indicated they had heard of the Henthorn case via media reports. Early on, three jurors were dismissed after they told the judge they felt they could not be fair to Henthorn and had already made their minds up about the case.

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Henthorn sat quietly, clad in a dark gray suit, taking notes and occasionally smiling.

Jackson told the potential jurors, “You can’t necessarily believe everything you read in the paper or see on TV.”

He went on to say that while he knows a great deal about the case, “I don’t have an opinion,” on the guilt or innocence of Henthorn.

The trial is scheduled to begin next Tuesday and prosecutors have submitted a lengthy witness list and have indicated they may have more than 300 exhibits.

Henthorn’s attorney, Craig Truman, has listed only a few potential witnesses and only a few exhibits. Truman was asked Wednesday if he planned to raise reasonable doubt in jurors minds through cross examination of prosecution witnesses. He declined to comment on his strategy. He was also asked if Henthorn would testify in his own defense. Truman again was non-committal on whether or not his client would testify about what happened.

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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.