Jeffery Trevino displayed an unusual calm in the aftermath of his wife's disappearance last winter and even referred to her in the past tense, according to witnesses who testified Thursday on the opening day of Trevino's murder trial.

That calm, according to prosecutors, masked an intense rage that Trevino harbored against his wife, Kira Steger, over her involvement with another man.

"The case you're about to hear is about rage," Assistant Ramsey County Attorney Andrew Johnson told jurors during opening statements. "It's about jealousy. It's about deception. It's about a cover-up.

"She wanted to leave, but he didn't want to let her go."

Trevino's attorney, John Conard, told the eight men and six women on the jury that the case against his client is built on circumstance and exaggerations about the evidence, including the authorities' claim that large amounts of blood were found in the couple's rented home in St. Paul.

"There is less than a thimble of [Kira Steger's] blood in the bedroom," Conard said. "That will become critical."

Details about Steger emerged as well, including a friend's testimony that girlfriends had become worried about her drinking and "staying out late," and that Steger was having an affair with a superior at work that she hid from close friends.

The case against Trevino, 39, began with the Feb. 22 disappearance of his wife, which led to intensive searches by police and volunteers who came from across the metro area. The searches continued through the late winter and spring until Steger's body was recovered from the Mississippi River on May 8. Trevino's arrest came well before his wife's remains were found, and he now stands charged with second-degree murder in Ramsey County District Court.

More than a dozen of Steger's family members and friends sat near the front of the courtroom Thursday as about half a dozen of Trevino's family members and supporters sat across the aisle. The packed courtroom included about five citizens who helped search for Steger's body.

'I thought I knew her'

Trevino reported his wife missing to police Feb. 24.

Friend Jazmine McLaughlin, who worked with Steger at Delia's at the Mall of America, said Trevino called her at the store on Feb. 23 and 24 about his wife's whereabouts.

Steger's car was found abandoned in a mall ramp Feb. 25 with what appeared to be blood on the trunk.

McLaughlin said that when she shared the news about the car's discovery with Trevino, "He handled it very calmly even though I was hysterical."

Steger's sister Keri Anne testified that when she called Trevino after Kira disappeared that he badmouthed his wife instead of asking for help finding her.

He also wanted to change Steger's Facebook password even though Keri Anne Steger said she lobbied against it in case her sister wanted to contact family members through the social media site.

Steger said Trevino told her that his wife had been drinking and partying recently.

" 'Well, Keri Anne, I thought I knew her,' " he said, according to her testimony. " 'I loved her.' "

"I asked him why he was talking about my sister in the past tense," Steger said, her voice straining with so much emotion that she had to repeat the sentence. "He got very upset."

Cut to the bone

In presenting the first arguments for the defense, Conard told jurors that autopsy results show that someone used a sharp blade to cut Kira Steger to the bone above her left eyebrow and that she was alive when the wound was inflicted. Such an injury would have bled "cups and cups" of blood, he said.

An abrasion in her mouth showed that she could have been smothered, and it appears that someone snapped one of her fingers back during an apparent attack, Conard added.

Meanwhile, Matthew Roff, who lived with Steger and Trevino and was home Feb. 21, testified that he didn't see or hear anything unusual inside the house that day.

The prosecution and defense are also set to clash on forensic evidence about the contents of Steger's stomach that will be presented later.

Steger had dinner with Trevino the last day she was seen alive, Feb. 21, and ate sushi and lamb meatballs, which would have been digested in five to seven hours, Johnson told jurors. But fish was found in her stomach, he said.

Conard, however, argued that Steger's small and large intestines were clean, indicating a more complete digestion.

That widens the window of time Steger could have been killed, and accommodates Trevino's story to police that she left between 8:30 a.m. and 9:30 a.m. on Feb. 22 to run errands.

Prosecutors believe she was likely killed between 12:30 a.m. and 2:30 a.m. that day.

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