(CBS/AP) SANTA FE, N.M. - Friends say Victoriano "Mo" Moises Byrne-Gonzales was an expectant father and art teacher who had just been promoted to assistant director at his Santa Fe preschool when he was fatally stabbed the night of Dec. 2, 2011.
His death was the tragic result of his effort "to do the right thing" when he saw a woman he didn't know getting beaten by her boyfriend, prosecutors said Thursday at the trial of the man accused in the attack.
Adrian Gonzales, 31, is charged in District Court with killing Byrne-Gonzales, 21. Gonzales is also charged with assaulting his girlfriend at the time, Natasha Romero, and stabbing and wounding Santiago Cordova, a friend of Byrne-Gonzales.
On Thursday, prosecutors played taped county jail phone conversations between Gonzales and Romero, recorded shortly after his arrest. Jurors heard an angry Gonzales tell Romero that he had just made "the ultimate sacrifice" for her.
According to the conversations recorded from the Santa Fe County Jail, Gonzales told Romero he was facing life in prison and that Byrne-Gonzales and Santiago Cordova were attacking him after his fight with Romero.
"You better love me for 30 (expletive) years of my life," Gonzales told a crying Romero, who apologized repeatedly for the altercation.
Authorities said Byrne-Gonzales was repairing his car when he heard Romero shout, "You're hurting me," and saw her and Gonzalez fighting at the Butterfly Springs Mobile Home Park in Pojoaque.
"We saw a male pounding on a female up against a wall," Chris Chavez, Byrne-Gonzales' brother-in-law, testified, saying they were fixing a car window at the time.
Byrne-Gonzales and Cordova quickly ran to the woman's aid, Chavez told jurors. But minutes later he saw Byrne-Gonzales return with the fatal wound to the neck. Cordova also was stabbed in the back, Santa Fe County sheriff's investigators said.
Hours later, Gonzales, a convicted drug trafficker, was arrested on Interstate 25 and charged with first-degree murder, aggravated battery with a deadly weapon and battery on a household member.
Defense attorney Megan Dorsey laid out a different scenario.
She said her client was acting in self-defense and had confused the men with two others who had burglarized Romero's mother's home.
Dorsey told jurors that Gonzales and Romero were arguing because Romero had been drinking heavily and Gonzales had threatened to end their relationship.
In her opening statements, Dorsey said Gonzales had been "confronted by two bullies" who tried to take the law into their own hands.
Gonzales only yanked Romero because a red truck was driving down the road and might have hit her, Dorsey said. The state countered that Gonzales had grabbed her and bit her ear during their argument.
During another recorded phone conversation, Gonzales is heard mentioning the truck to Romero, who said she didn't remember the vehicle.
"My ear hurts," Romero tells Gonzales on the phone. When Gonzales asks her why, she said, "I'm not going to say it on the phone."