That's the question prosecutors and defense attorneys are posing to jurors in the murder trial of Adam Karr, the party host accused of stabbing Yazzie to death on July 31, 2012.
Karr, 27, is charged in 3rd District Court with first-degree felony murder and second-degree felony obstruction of justice in Yazzie's death. He faces up to life in prison if convicted of murder.
Defense attorney Richard Mauro said Yazzie had done more than annoy Karr he had threatened him.
Yazzie told party-goers he was an experienced knife fighter and knew mixed martial arts, Mauro said. He bragged about gang connections, and had been throwing mock punches at Karr's face, the lawyer added.
"It was time for [Yazzie] to leave," Mauro told the jury. "Adam picked up a knife because he was afraid."
Throughout his opening remarks Wednesday, Mauro emphasized Karr's connection to the people around him and the place where the stabbing took place.
At a March preliminary hearing, Mauro characterized Karr's actions as legal and reasonable under a defense of habitation law passed by the Utah Legislature in the 1980s. According to that law, a person has the right to defend their home from an intruder by use of lethal force if they perceive the intruder will cause them bodily harm or will commit a crime in their residence.
But prosecutors dismissed that argument. If Yazzie was a problem, they said, Karr made it worse by picking up a knife.
Prosecutors said Yazzie was on his way out when he and the defendant's younger brother, Ammon Karr, began to argue. As the younger Karr walked Yazzie off the premises, prosecutors said, words escalated to blows.
That's when Adam Karr allegedly jumped into the fracas, pulled out a knife concealed behind his back and stabbed Yazzie until the young man could barely walk, prosecutors told the jury.
"[Police] find Kaleb Yazzie stretched out in an alley," prosecutor George Vo-Duc said. "His shirt was soaked in blood."
Two young men who had attended the party at which Yazzie was killed, at the home near Girard Avenue (560 North) and Desoto Street (40 East), testified Wednesday. They had been the most sober of a mostly underage group that was drinking heavily and experimenting with illegal drugs.
Both witnesses said they had seen Adam Karr carrying a knife as his brother led Yazzie out the front door. Both said they heard the defendant proclaim, "I want to shank somebody" before the stabbing occurred.
Both told tales of Yazzie knocking a baseball cap off the defendant's head and making threats to both brothers.
"I didn't know what to do," said Brandon Harris, 19, explaining why he didn't immediately call police. "I was scared."
Ammon Karr, who also was charged in this case, pleaded guilty in November to second-degree felony obstructing justice. A count of third-degree felony aggravated assault was dismissed. He was sentenced in January to 195 days in jail in lieu of a possible 15-year prison sentence, and has served 90 days house arrest. He is now serving 36 months of probation.
A 17-year-old accused of dragging Yazzie's bleeding body out of the yard and down the road to an alley, where he stomped on Yazzie's head, was sentenced in November to remain in a juvenile facility until he turns 21 or is paroled. He agreed to testify against Karr at this week's trial as a condition of his plea deal.
Yazzie's family hopes a trial will ensure Adam Karr does not get off so easy. More than a dozen family members attended Wednesday's proceedings.