VANCOUVER, Wash. — Matthew Denni is an Army Reserve soldier who went to Iraq, got shot and was sent home to heal. But on a late night in March he pulled a hand gun from his dresser and killed his wife, Kimberly, with a single shot.

At his trial, which began yesterday in Clark County Superior Court, the prosecution and defense agreed on the chain of events that night, which Denni recounted in a taped confession to police.

But what is in dispute — and looms as the core issue in the trial — is Denni's state of mind the night he killed his wife, stuffed her body in a footlocker and placed it in the back of their blue Ford Aerostar van.

Was it a clear-cut case of premeditated murder, as Clark County Deputy Prosecutor Mike Kinnie argued yesterday before the jury. Or was this a crime of passion, a sudden, spontaneous act, fueled by the trauma Denni experienced in Iraq and the stress of a rocky homecoming, as Thomas LaDouceur, Denni's attorney, maintained.

"Now he has to be held accountable, but this wasn't something that he thought about a month, a week, a day or a minute earlier," LaDouceur said. "It was murder ... but not premeditated."

Denni, 39, is one of a small group of soldiers who have returned from combat and killed their wives. A trio of Special Operations soldiers based at Fort Bragg N.C., who returned from Afghanistan in 2002, killed their wives. All three men committed suicide. Last year, a Fort Lewis soldier who returned from Iraq confessed to killing his wife.

For some, these cases underscore the importance of making mental-health counseling widely available to returning veterans.

"This was a wake-up call," said Sgt. Myron Denny, a friend of Denni's, who served with him in the 671st Engineer Company, a Portland-based Army Reserve unit that returned from Iraq last February.

A month after Denni's arrest, Denny said in an interview, his unit was visited by several Army mental-health counselors. The counseling was a good thing, Denny said, "but should have been done when we got home — not months after we'd been home."

In opening arguments, LaDouceur cited Denni's Iraq experiences as context for understanding his violent outburst the night his wife died. But it will be up to the 12-person jury to decide whether his Iraq experience, or the stress of his homecoming, altered the seriousness of the crime.

Denni is charged with premeditated murder in the first degree, which could result in a prison sentence of more than 25 years. His attorney said he should face a charge of second-degree murder, a lesser crime that would make him eligible for a lighter sentence.

Denni had no prior criminal record and has been described by friends and neighbors as a quiet man who kept his feelings to himself. His unit was part of the invasion of Iraq. After the fall of Baghdad, it set up a tent camp and was there during the early months of the occupation.

During his stint, Denni served as a supply sergeant and helped ensure that the unit had enough ammunition, food and clothing. Denni saw death and destruction and "lived in constant fear," LaDouceur said.

In November 2003, a loaded rifle accidentally discharged and a bullet struck Denni in the leg, according to LaDouceur. Wounded, Denni returned home several months before the rest of his unit returned in February 2004.

Denni rejoined his wife and their young daughter. The family rented an apartment in Battle Ground, a small city north of Vancouver.

Their landlord — Wayne Redjou — yesterday testified that Kimberly was a lively, sociable woman who enjoyed frequenting garage sales and second-hand shops. Though she seemed to have a very different personality from her more reserved husband, Redjou, who lived next door, said he never heard the couple have any big fights.

But in the courtroom, the prosecution played taped excerpts of Denni's May 31 confession, when he described the couple's final night together. They went out dancing, shot some pool and sipped beers, Denni said. But once back at their apartment, a bitter argument ensued.

Denni said their talk grew heated over his wife's alleged affair. Denni said his wife followed him into their bedroom and declared she was leaving him for the other man.

At that moment, Denni said, he reached into his dresser, pulled out his gun and shot his wife.

Asked if he cried at the time, Denni said, "I don't think I really have stopped since then."

Still, Denni said, he was too scared to call 911. Instead, he put her body in a green footlocker, which was left for weeks in the couple's van. He told friends that Kimberly had gone back east to stay with her mother.

Finally, on a warm day in May, Redjou testified that he was out mowing the lawn when he noticed a foul smell coming from the van. Assuming it was spoiled meat, Redjou said, he went to talk to Denni, who said, yes, it was spoiled groceries. Redjou then helped Denni bury the footlocker in a field on his property.

At the time, Denni appeared cool and calm.

When the job was done, Redjou testified, "I said, 'There — that's easy.' "

"He said 'Yup.' "

In late May, Battle Ground police and Clark County detectives got a tip and came out to dig up the footlocker. But what they found was a second footlocker, which did contain rotting food. Denni later told police that he had switched the footlockers, placing the original with his wife's body back in the van.

Police that same night found the locker in the van, stowed beneath a tarp, according to yesterday's testimony.

Detectives said they tracked down Denni, who was staying at a church camp in Skamania County with a new girlfriend. Confronted with the news that police had discovered his wife's body, Denni confessed.

Detectives and police say he waived his rights, including having an attorney present during their interrogation. He gave police numerous details and drew a map of the crime scene.

His trial continues this week and is expected to include more detailed testimony about Denni's time in Iraq.

Hal Bernton: 206-464-2581 or hbernton@seattletimes.com

Researcher Gene Balk contributed

to this report.