A Border Patrol agent's past arrest for military desertion, which he didn't disclose when applying for a job with the agency, is relevant at his murder trial in the cross-border shooting of a Mexican teen, federal prosecutors argued in court documents asking a judge to allow the evidence.

The U.S. Attorney's Office for Arizona filed the motion Thursday after defense attorneys sought to exclude the military and job performance records of defendant Lonnie Swartz.

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Swartz has pleaded not guilty to one charge of second-degree murder in the 2012 death of 16-year-old Jose Antonio Elena Rodriguez.

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Swartz is accused of firing through a border fence from Nogales, Arizona, into Nogales, Sonora, Mexico, in 2012 and killing 16-year-old Jose Antonio Elena Rodriguez.

[RELATED: New details emerge in fatal border shooting of Mexican teen (July 26, 2016)]

He is being tried in federal court in Tucson.

The records say Swartz enlisted in the military in 1995 at age 19 and went AWOL two months later. He was arrested in Las Vegas in October 1997 and discharged in lieu of trial by court-martial four months later.

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Prosecutors say Swartz omitted his desertion and arrest when applying to work for the Border Patrol. Instead, he stated that he served in the Army for one month before quitting.

"The jury should be apprised of those statements in evaluating his credibility on the witness stand," the prosecutors' request states. "The fact that these statements were made when he applied ... make them particularly germane to this case which involves his conduct as a Border Patrol agent."

[RELATED: Judges refuses to oust prosecutors from border shooting case]

Defense attorney Sean Chapman has said Swartz's military history has no bearing on whether he fired his weapon with criminal intent in the death of Rodriguez.

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Chapman cited the same reasoning while calling for 230 pages of internal, personnel records to be excluded as possible evidence. The Border Patrol records include field observation reports, performance evaluations and results of proficiency tests.

Chapman did not immediately return a call seeking comment Friday.

Prosecutors accused the defense of being too broad with its requests.

Swartz has said Rodriguez threw rocks at him, endangering his life. The teen's family denies that claim, saying he was walking home after playing basketball with friends.

Swartz is also facing a civil rights lawsuit filed by the ACLU on behalf of the boy's mother.

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