Jeffery Trevino's military service, previously clean criminal record and tenets of the U.S. Constitution should grant him a lower-end prison sentence for the murder of his wife, his attorney argued in a recently filed memorandum.

A sentence of about 10½ years in prison fits Trevino's second-degree unintentional murder conviction, wrote his attorney John Conard, not the prosecution's request for 30 years.

"Given Trevino's service to his country, and exemplary behavior for the first 39 years of his life, the minimum guideline sentence of 128 months is certainly appropriate," Conard wrote.

A jury convicted Trevino, 39, in October of second-degree unintentional murder in the death of Kira Steger, 30, and acquitted him of the more serious charge of second-degree intentional murder. The conviction has a guideline sentence range of about 10½ years to 15 years in prison, with 12½ years being the midpoint.

Assistant Ramsey County Attorney Andrew Johnson filed a memo Wednesday requesting that the court sentence Trevino to 30 years in prison because of "aggravating factors" in the case, including the fact that Steger's body was missing for two months.

Johnson argued that Trevino kept silent about the whereabouts of Steger's body, causing trauma to the family.

Conard argued that Trevino was exercising his Fifth Amendment right.

"Jeffery Trevino was arrested within a few days of his wife's disappearance," Conard wrote. "At that time, if not before, he had an absolute right to remain silent, and to expect that his silence would not be used against him. Fundamentally, he had no affirmative duty to disclose information which would incriminate him, assuming that he had such information to give."

Although Trevino was convicted of the murder, there have been no findings by a jury or judge that he disposed of Steger's body and intentionally concealed it. District Judge Leonardo Castro will rule on that matter when Trevino is sentenced on Nov. 25. Aggravating factors can be used as grounds to increase a prison sentence beyond state guidelines, which is what prosecutors are seeking in this case.

Johnson and Assistant County Attorney Richard Dusterhoft argued at trial that Trevino killed Steger in their St. Paul home in February because she wanted a divorce while he wanted to save their marriage. Steger was having an affair with a male co-worker at the time.

Steger was last seen alive in public with Trevino and went missing after the couple's date night at the Mall of America on Feb. 21. She texted her male co-worker throughout the evening. Her body was discovered in the Mississippi River on May 8.

Conard also argued that if prosecutors believed Trevino concealed Steger's body, they could have charged him with that crime, interference with a dead body, instead of addressing it after trial.

"… Trevino did not act in a particularly cruel manner in the commission of the homicide, and did not damage or dismember the body afterward," Conard wrote.

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