Brianna Denison Trial: Prosecutors Seek Death Penalty

James Biela (AP)

RENO, Nev. (CBS/AP) Prosecutors say that a man obsessed with women's thong underwear started out raping women, and ended up killing one. Now, Prosecutors are trying to convict James Biela, and are seeking the death penalty for his heinous alleged crime.

PICTURES: Brianna Denison's Life Ends in Brutal Rape and Murder

James Biela, a 28-year-old trained in martial arts, is accused of the sexual assaults of two women in 2007 near the University of Nevada, Reno and the murder of college student Brianna Denison in 2008. He is charged with three counts of sexual assault and one count each of kidnapping and murder.

Deputy District Attorney Chris Hicks said, in his opening statement to a seven-man, five-woman jury, that Biela "graduated from serial rapist to murderer," and that after DNA and other forensic evidence is presented, jurors will inevitably see the truth of Biela's guilt.

Brianna Denison (Personal Photo)

But Public Defender Jay Slocum encouraged jurors to view the evidence with the "cold light of reason." He said DNA evidence was not conclusive, and that while authorities say they've linked the three crimes to a single assailant, each has "very distinct facts."

PICTURES: Brianna Denison's Life Ends in Brutal Rape and Murder

Brianna Denison, a 19-year-old from Reno, disappeared while sleeping on a couch at a house near UNR in January 2008. Her body, covered by a discarded Christmas tree and wearing only socks was found three weeks later in a snowy vacant lot in south Reno. Beneath one of her legs were two pairs of women's thong underwear. Forensic experts believe it was used to strangle her.

Biela is also accused of raping a woman in a UNR parking garage at gunpoint in October 2007. Another woman was kidnapped two months later and was assaulted before her attacker drove her home and told her not to call police, authorities said. In both of those crimes, Hicks said, the women were attacked from behind and the assailant kept their underwear.

The first woman threw away the clothes she was wearing and didn't report the crime until after Denison's abduction, but after Biela's arrest she identified him as her attacker.

The second woman, an exchange student whose native language is Mandarin, was the first witness called Wednesday, and told jurors how she was grabbed from behind by an attacker who covered her mouth and choked her to unconsciousness; she was also forced to perform sexual acts before being driven home.

Biela was arrested in November 2008 after an anonymous tip that led authorities to his ex-girlfriend, who reportedly confided to a friend about finding two pair of women's thong underwear in Biela's truck. Police later matched his DNA to that found on Denison's body.

The trial before Washoe District Judge Robert Perry is expected to last about three weeks.

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