A man who pleaded no contest to voluntary manslaughter for the killing of a Pomona police SWAT officer who was helping to serve a search warrant at a San Gabriel house where the defendant and his family lived more than eight years ago was sentenced Tuesday to 10 years in prison.
David Martinez, 44, was acquitted in two separate trials — first of first-degree murder and then of second-degree murder stemming from Officer Shaun Diamond’s October 2014 shooting death. Jurors in the most recent trial deadlocked last October on two other charges — the lesser count of voluntary manslaughter and assault with a firearm on a police officer.
Martinez pleaded no contest Nov. 30 to both of those counts and admitted gun allegations.
Martinez — who waived his right to a third trial — made an open plea to the court, with no stipulation announced in open court on what sentence he would face.
Defense attorney Brady Sullivan said in November that he would ask for a 10-year sentence — the bulk of which Martinez has already served in custody.
Diamond — who was 45 years old and a 16-year law enforcement veteran who also worked for the Los Angeles and Montebello police departments — was placed on life support and died a day after the bullet severed his spine and shattered his lower jaw.
Martinez has remained jailed since he surrendered to police shortly after the shooting, telling officers, “I’m sorry. I didn’t know you were the police. I thought you were the Mongols.”
Martinez testified in his own defense during both of his trials, saying during his first trial that he fired a “warning shot” from his shotgun because he feared members of the Mongols motorcycle club — an organization to which he belonged — were trying to break into the home he shared with his parents, his girlfriend, their two young children and his adult sister.
The defendant told jurors he was startled to hear screaming after firing the shot, turned around, dropped the shotgun, laid down and said he was sorry.
“I kept saying I was sorry. I didn’t know it was the police,” Martinez testified in 2019. “I thought it was the Mongols. I would never fire at police or law enforcement ever. I have family that’s (in) law enforcement.”
He maintained during his first trial that he “shot to protect my family” and that there was “no target.”
Police went to the house early that morning to serve a search warrant as part of an ongoing investigation by a task force into the Mongols, Deputy District Attorney Hilary Williams told jurors during the retrial.
Diamond had turned his back to walk off the steps with a heavy piece of equipment that had been used to open the screen door and was shot by Martinez in the back of the neck with a 12-gauge shotgun, the prosecutor told jurors during the trial. None of the other officers present returned fire, the prosecutor said.
“You don’t get to just shoot somebody on your doorstep,” Williams told jurors, arguing that there was no way the shooting occurred in self-defense as Martinez and his attorney contend.
The deputy district attorney told the panel that it was “irrational on every level” to shoot a law enforcement officer in front of some of the defendant’s own family members, but said the defendant was “high on methamphetamine” at the time of the shooting.
Martinez’s attorney called what happened a “tragic accident” and said Martinez was lawfully defending his family after seeing the barrel of a gun.
“And it was reasonable. … The law says it’s reasonable to defend your family, your home and yourself,” Sullivan told the panel.
Martinez’s lawyer said it was not reasonable to believe Martinez would deliberately fire a shot at police and put his entire family at risk inside the home.
“He didn’t know it’s the police. He thinks it’s an intruder,” Sullivan said.
The defense attorney called the SWAT team’s operation that day “completely unnecessary” and contended that the officers’ warnings that they were there to serve a search warrant were drowned out by noise being made by the SWAT team as they tried to get into the house and a locked gate. The prosecutor countered that the warnings were given before and during the efforts to breach the home and gate.