Yup, and a fellow officer asked twice if he should be moved to the recovery position, also in the training. Dude refused, and held it 3 minutes after he had no pulse. It's called that and it's effective because it places the suspect in extreme bodily stress, so much so that they have to be placed in a recovery position, especially if there's possibly other factors such as drug use or physical stress from a struggle before hand, and all that is extensively covered in their training too. Both autopsies confirmed that he was killed from the hold, yup he was also on drugs but would have been fine without meeting the cops. He either didn't know shit about the move he executed, or he knew exactly what he was doing, and did it anyways. The Supreme court today rejected his appeal.
I get that being a cop is hard as hell, but the job requires some common sense and compassion for your fellow man, no matter how much of a pain in the ass they are. They are innocent til proven guilty, and he's not the one to make that call. When he goes limp and has no pulse, that would have been a good time to reassess the situation, but he didn't do that, not for another 3 min. Saying he didn't die of asphyxiation makes zero sense either, most everyone knows proper chokeholds work by applying pressure to the blood vessels. Even short drop hanging and garroting kill by restricting the blood flow, not by blocking the airway.
While not being a full on choke, having your hands tied behind your back and a knee on your neck (we'll even say upper shoulder back area just for discussion, but it was found to be his neck) places a ton of pressure on those blood vessels, heart, and lungs. 10 min of that, especially after his drug use (mentioned in the original call), resisting arrest, and subsequent panic attack was pretty much certain to cause a heart attack, that would probably kill most people. As a police veteran he would have most definitely known this, so he was charged with murder because he ended a life knowingly and maliciously, the refusing to let up as he goes unconscious is the smoking gun.