This is Stephon Clark, lying on the ground, motionless after two Sacramento police officers shot him seven times. He was a 22-year-old father of two boys. An unarmed black man. Killed in his own backyard. And it all happened in just 23 seconds. We’re going to break down those 23 seconds and look at five critical moments. Our frame-by-frame analysis reveals a series of split-second decisions and errors, and examines how they ended in Clark’s death. A warning: It can be hard to watch. First, let’s play the whole encounter. Pay attention to how quickly it escalates. It all starts earlier around 9:10 p.m., when a resident calls 911 and reports that someone is vandalizing cars. Then, 16 minutes later, a police helicopter spots a suspect. This is Stephon Clark. The police footage doesn’t show Clark break a window. But the police say they believe he was responsible for the reported vandalism. Clark jumps a fence into this yard. He lived here with his grandmother, although there’s no reason to think that the police knew this. Moments later, we see two police officers approach the front of the house. Police have not confirmed the officers’ identities, so we’ll call them Officer 1 and Officer 2. The helicopter guides them toward Clark. Officer 1 has his gun drawn before he encounters Clark. We slowed down and brightened this clip to see it more clearly. This is just before the officer first shouts, starting the crucial 23 seconds as the officers begin pursuit. Clark is standing along the side of the house, while the officers are at the front. Officer 1 sees Clark and shouts. Clark runs farther into his backyard. He moves under a covered patio and stays there for the next 13 seconds. The officers chase Clark and run around a blind corner, breathing hard. Their speed may have robbed them of a chance to de-escalate the situation from a safe spot, which would be in line with their department’s instructions. The chaos of the full-on pursuit could have been a factor in the next critical moment, when one of the officers mistakenly thinks that Clark has a weapon. Officer 1 is now about 40 feet away from Clark. We’ll freeze on this frame. It’s difficult to see, but right here, this is Stephon Clark facing Officer 1. We can tell he’s stopped and facing the officer, but we can’t see much else, including whether he has anything in his hands. Here’s the moment from the helicopter’s perspective. Less than two seconds after coming around the corner, Officer 1 shouts the word “Gun.” So, why in that brief moment did the officer conclude that Clark, who was unarmed, had a gun? We don’t know. Both officers backtracked behind the corner and then looked back around it. Officer 1 again concludes that Clark is armed. And immediately after that, his partner decides to fire. Why? Possibly because he saw Clark’s movements. Remember, Clark had been stopped, but as the officers retreat, he begins moving in their direction. When they look around the corner again, he’s closer, around 25 feet away from the officers and continuing to move. Clark is stepping through a narrow space between a picnic table and the house, likely turned and not directly facing the officers. We drew this conclusion in part by comparing the body camera to this picture of Clark from earlier in the same day. Notice the pants with white stripes — the same ones seen in the body camera. But nothing in the videos can tell us why Clark moved. Overhead from the helicopter we see him as well. That small cluster of white pixels. That’s all we can see of Clark before shots are fired. Less than a second after Officer 1 called out a gun for the second time, Officer 2 fires the first series of five bullets. After a short pause, both officers shoot a combined 15 more times. Let’s look at that again from the helicopter. The first volley is fired while Clark stands. He falls to his hands and knees. He’s still moving as the second round of shots begins, and then, by the time it’s over, he’s motionless. So, which shots killed Clark? The ones fired while he was standing or those fired while he was on the ground? In early May, the Sacramento County coroner released its autopsy report, concluding that Clark was shot seven times. By combining the report with our analysis we determined that Clark was struck in his left leg while still standing, a non-lethal shot. He was also struck six more times, all on the right side and back. These shots broke his ribs, fractured his spine, lacerated his heart, perforated his lungs and killed him. Given Clark’s position, orientation and movement, these last six shots almost certainly hit Clark while he was falling or lying on the ground. We don’t know exactly how long it took these wounds to kill Clark, but we do know that there was a significant delay before any medical aid was given. “Show me your hands.” “Let’s see your hands.” After they stopped firing, the officers don’t approach Clark. They talk to either each other or to Clark’s unresponsive body, which they still consider a threat. “You all right, you hit?” “Yeah, I’m good.” Two minutes after the shooting, other officers arrive. “You can’t see his hands, right?” The police discuss using a body bunker, a shield to protect themselves from gunfire. “Three-Sam-five if you can head this way, we could use a body bunker before we detain him.” Almost three minutes after the last shot, the police identify themselves for the first time. “Hey, can you hear us?” “Police Department, can you hear us?” “We need to know if you’re OK. We need to get you medics, but we can’t go over to get you help unless we know you don’t have a weapon.” Officer 1 describes the moment when they fired. “He came up and then he, he kind of approached us hands out. And then, fell down.” Four minutes and 50 seconds after the shooting, officers approach Clark. “One of you guys want to go hands, cover ’em, I — oh, fuck.” They handcuff him, which is a standard practice. And when they roll him over, his cellphone is lying under his body. This suggests a possibility: that Clark had the phone in his hand and that’s what the officers mistook for a gun. The police now have the phone but have not said whether he was recording. “Give me a light, we’ll start CPR.” “All right.” Six minutes after the last bullet was fired, officers not involved in the shooting give first aid. Clark is pronounced dead at the scene. Officers 1 and 2 step away and mute their cameras. “Hey, mute.” We can no longer hear what they’re discussing. Shortly after the shooting, the Sacramento Police Department updated its guidelines. Officers are now required to record why they mute or turn off their cameras.