My mother always said there are two sides to every story. In this story, there are two sides to the same door. It’s the wooden front door of the Martinez two-bedroom, one-story residence in Montebello, California. On one side of the door, a shot was fired. On the other side, a man was killed.

Outside of the door, on the evening of October 28, 2014, 45-year-old Pomona Police Officer Shaun Diamond was called to take part in a SWAT operation. His team was tasked with serving a search warrant to a house inhabited by David Martinez, a member of the Mongols Motorcycle Club. The operation was considered high-risk due to the Mongols’ association with a wide range of criminal activities including the use of illegal firearms, meth trafficking, robbery, assault, and murder. In accordance with procedure, officers rammed the padlocked gate of the home and entered the property while announcing their presence. Corporal Richard Aguiar and Diamond breached the outer metal security door of the home with a push-pull device called a “ripram.” Diamond turned to discard the device as someone inside the home opened the inner, wooden door. On the other side of the door, Martinez fired a round from a twelve gauge shot-gun that struck Diamond in the back of the neck. The brutal injury killed him a few hours later.

It’s May of 2019, five years after that fatal evening, and Martinez is on trial for the murder of Diamond. Diamond is deceased but his presence is palpable in court. The outpouring of support from the police for the fallen officer is effusive. Diamond’s friends from law enforcement show up at court to sit broad shoulder to broad shoulder in the gallery. Their silent allegiance is evident by their gleaming badges and leather gun holsters. The day that Martinez takes the stand the court is so packed with officers that several are forced to lean against the back wall without a seat. Judge Charlaine Olmedo looks out into the gallery at the stoic men and smiles softly. “I’ve never seen so many grey suits.”

Seated among these grey suits is a woman in her late 20s with short, brown hair, large eyes and a jean jacket; Diamond’s daughter, Margo. She attends court every day, taking notes on the proceedings in a spiral bound memo pad. Margo sits in the gallery — shoulders back, craning her neck to see the witness stand. She listens for days to testimony about her father’s death. The gun that shot him, the impact of the bullet that severed his arteries, the sounds he made as he died.

When the medical examiner testifies, the prosecutor nods back at Margo before showing a photograph of Diamond on the coroner’s table. Margo stops taking notes. In the face of her father’s lifeless body, she keeps her lips tight and her chin high. Margo has her father’s nose.


Inside the door on the evening of October 28, 2014, 41-year-old termite inspector David Martinez was finishing up some inspection reports in the study of his parents’ house. After a motorcycle accident kept him from working for several months, he had moved back home with his parents, his sister, Brenda, who has Down syndrome, his common-law wife, Sandra, and their two young children. Martinez belonged to the Mongols Motorcycle Club — he had the full patch on his jacket and everything. But according to Martinez, he only got into it for the motorcycles. And the brotherhood. Now he was rethinking his membership. Sandra didn’t like him hanging out with the Mongols and the “brotherhood” that Martinez was promised had become hostile. He reported receiving vague but threatening text messages for avoiding gang activities.

David Martinez

At 3 am, Martinez finished his reports. He climbed into bed with Sandra and was just about to fall asleep when he heard a banging noise that rattled the whole house. Martinez grabbed the shotgun that he kept by the side of his bed and ran to the living room. Here the banging was even louder and the family’s four dogs were barking. Martinez saw his father, Arturo, by the door. He called out for his dad to wait, but Arturo had already turned the knob. The door opened to reveal the barrel of a gun pointed inside the home. In a split second, Martinez fired one shot into the darkness. The bullet hit Arturo. And on the other side of the doorway, that same bullet hit Diamond.

Arturo survived his gunshot wound — a superficial injury to his arm. For Diamond, the shot was fatal.

It’s May of 2019, five years after that fatal evening and Martinez is on trial for the murder of Diamond. Martinez sits at his counsel’s table, clean-shaven with short black hair and a muscular frame. His tattoos are concealed beneath a light-pink, collared shirt. When the prosecution gains momentum, Martinez fidgets. His idle hands find a note-card that he folds with small, sharp creases. Occasionally he looks back into the gallery.

The Martinez family is there to smile back at him. Several of his siblings sit side by side, dressed in sleek, stylish clothes. They could easily belong in the audience of a college graduation, but there are no caps or gowns here; their brother is being tried for murder. During the final days of proceedings, Arturo and Guadalupe, Martinez’s mother, join the siblings, including his sister, Brenda. Arturo wears a faded blue button-up. He stares straight ahead. His frame is solid and his countenance is one of pure endurance. Guadalupe is slumped in her seat, staring at her black loafers. A gold chain hangs around her neck, just visible beneath her thick, auburn hair. Brenda sits between them — a Yu-Gi-Oh! comic book and a pack of saltines to her side. She smiles at a picture of a Chihuahua in her hand. When Guadalupe’s shoulders shake, Brenda sets aside the picture and rubs her mother’s back. David waves with a small, sad smile from the counsel’s table. Brenda waves back.


These two narratives converged when the door opened. In less than three seconds the inside story and the outside story were shattered with a gunshot. Now there is no door; just benches in a courtroom filled with people in pain.