Trial Begins in Corona Love-Triangle Killing : Crime: Jury must decide whether ex-Anaheim officer shot his wife’s boyfriend in self-defense.

They were friends who became rivals for the same woman, a love triangle that exploded in December when Thomas Minn fired two bullets into Paul Hangen’s head.

Minn, a 37-year-old former Anaheim motorcycle officer, now faces a jury whose job will be to decide not whether he killed his one-time housemate, but why.

“This is no whodunit. Tom Minn shot the guy,” said Minn’s defense attorney, James A. Stotler, during opening statements Monday in Riverside County Superior Court.

The prosecutor and defense lawyer agree on the basics. They agree that for months, Minn watched as a love affair blossomed between his wife, Elian Schonberger, then 36, and Hangen, who was living in the couple’s home. They also agree that Minn fatally shot Hangen on Dec. 16 on a dirt road half a mile from Minn’s home during a showdown over the relationship, while Schonberger waited for Hangen to pick her up for a night of dancing.

But jurors must determine whether Minn attacked or fired in self-defense as the argument escalated.

Hangen, 28, was found sprawled face-down across the seat of his pickup truck, his head dangling near the open passenger door and his cowboy hat on the ground. Two spent .45-caliber casings from Minn’s service revolver were found nearby, said Deputy Dist. Atty. Kevin J. Ruddy.

Ruddy, holding a blown-up photograph of the bloody murder scene, said the bullets were fired into the back of Hangen’s head from six to 12 inches away.

But using the same photograph, Stotler told jurors that Minn was fleeing the truck and fired because he believed Hangen was about to pull a gun from under the seat. He said Hangen, whose left arm was partially under the seat when he was discovered, was known to keep a gun there. Police found no gun under the seat.

Minn, who has resigned from the Anaheim police force, showed no emotion as the attorneys filled in the details of a tempestuous six-year marriage that by the end was peppered by his wife’s violent outbursts and undisguised affection for Hangen.

Hangen and his parents, who met Minn and Schonberger in 1992, moved into the Minn home in Corona in 1994 for two months while waiting for their new home to be readied. When Hangen’s parents moved out, he remained at the couple’s home and the trio became fast friends.

But the friendship between Hangen and Schonberger became a romance. Stotler said they gave each other love pecks and hugs in front of Minn and his stepson, Schonberger’s 13-year-old son. The boy testified on videotape that he told his mother her behavior was wrong.

Schonberger repeatedly denied the affair and insisted the two were just friends, Stotler said. But the defense lawyer said Schonberger and Hangen eventually became intimately involved.

By the time of the slaying, the marriage was falling apart. Minn and his wife took separate bedrooms and spoke of divorce, and Schonberger bit and kicked Minn during arguments, according to the boy’s testimony. Schonberger had applied for her own apartment on the morning of the shooting.

Hangen, who no longer lived at the Minn home, frequently visited Schonberger. The two men became bitter enemies. Stotler told jurors Hangen referred to Minn as “fat boy” and said he wanted to kill him. But Ruddy said during a hearing without jurors present that Hangen lived in fear of Minn.

Hangen was to pick up Schonberger for an evening of dancing but was intercepted by Minn about 7 p.m. Stotler said Minn took a weapon because he feared the discussion might turn violent. Minn returned home after the shooting and took a shower, the lawyers said.