SIOUX CITY -- The prosecution reiterated in a new court filing that evidence conclusively shows that Tran Walker stabbed Paiten Sullivan and Felipe Negron Jr. to death.
Facebook messages the defense has called outdated also show Walker's motivation for revenge on Sullivan for breaking up with him, First Assistant Woodbury County Attorney Mark Campbell said in a rebuttal brief.
"The Facebook records documented what Walker's thoughts and feelings were toward Sullivan and how Walker viewed his relationship with Sullivan," Campbell wrote in his rebuttal to the defense's closing brief.
Filed Wednesday, Campbell's brief was the final filing in the case, which now will be considered by District Judge Tod Deck. Walker waived his right to a jury trial and chose to have Deck decide his fate.
At the conclusion of the three-day trial on May 6 in Woodbury County District Court, Deck said he would reach a verdict as soon as possible once all closing briefs were filed.
Walker, 19, of Sioux City, has pleaded not guilty to two counts of first-degree murder for the Jan. 28, 2018, deaths of Sullivan, 17, and Negron, 18, both of Sioux City. If found guilty as charged, Walker would face a mandatory sentence of life in prison without parole.
In their closing brief, public defenders Jennifer Solberg and Laury Lau attacked the prosecution's use of Facebook messages to attempt to prove that Walker planned to kill Sullivan because they were breaking up, saying the messages, sent months before the incident, showed nothing more than Walker feeling "teen angst about not being with his girlfriend."
Campbell countered that the Facebook messages were similar in tone to text messages Walker sent to a friend six days before the slayings in which he said he needed closure with Sullivan and that he had to "get her out of the way."
Campbell rebutted a defense argument that Walker did not plan or have the specific intent to kill Sullivan and Negron. Campbell referred to his initial closing brief in which he said Negron had identified Walker as his attacker before he died and that Walker admitted during an interview with police that he stabbed Sullivan and Negron both inside and outside a PT Cruiser while they were parked near South Cecelia Street and Jay Avenue.
Finally, Campbell brushed aside a defense argument that Walker had mental illnesses that prevented him from forming the specific intent to commit the crime, one of the elements necessary to prove first-degree murder. The defense has never filed a diminished capacity defense, Campbell said, and Walker's actions the night of the deaths were not consistent with someone with a mental condition. Campbell pointed out that Walker fled the scene when witnesses approached, threw away the knife he was carrying as he ran away and then was able to lead police to it the next day.
"... sufficient evidence exists in the current trial record to show that Walker's claim of a psychological defense is without merit," Campbell said.
Trial evidence showed that Sullivan was stabbed 43 times and Negron 17 times. Sullivan bled to death after a carotid artery in her neck was sliced, and Negron died of excessive bleeding from a stab wound through his chest that punctured his heart. Campbell has argued that the number of stab wounds is proof that Walker acted with malice and intent to kill.