SAN FRANCISCO (KGO) -- Police in California are not allowed to use chokeholds, but certain departments allow officers to subdue a suspect with a technique called carotid restraint.
In a split second, it's hard to tell the difference between a chokehold and a carotid restraint. Yet the effects are very different. A chokehold cuts off the windpipe. A carotid restraint involves squeezing the arteries.
Krav Maga Extreme owner and instructor Gaby Gliksman started martial arts training as a child. He now works with local police officers. He considers any move involving someone's neck highly skilled, requiring careful training and supervision.
"You can put somebody out in a few seconds," said Gliksman.
He demonstrated a chokehold, which involves an arm across someone's windpipe.
In a carotid restraint the arteries on the side of the neck are squeezed to restrict blood supply to the brain. In under a second, it is possible to feel the effect.
Krav Maga student Cary Tanaka says a chokehold is much worse. "You feel that touch against the trach, the windpipe area, it's really uncomfortable," he said.
Both the Oakland and San Francisco police departments allow officers to use carotid restraints. But Lieutenant Henderson Jordan with Oakland's police department, hasn't tried one since his training at the academy.
"Basically it's deemed as lethal force, it's one of the highest levels of force in the department," explained Lt. Jordan.
In April, Cisco Lutu captured video of an SFPD officer taking down a handcuffed fan at the Giants home opener.
"There were people around saying 'You're going to kill him!' so it was a hard thing to watch," said Lutu.
The SFPD would not speak on camera, but did issue a statement that reads in part: "We do not use the chokehold/neck restraint. We use the carotid restraint."
In the video, it is you can see the suspect's neck fits in the crook of the officer's elbow - consistent with a carotid restraint.
By contrast, the video of Eric Garner's arrest appears to show the officer's arm across Garner's neck, which is consistent with a chokehold.
Ultimately, Gliksman says both moves can be dangerous. "The best thing is try to avoid it, de-escalate the situation, that's what we're going for," he said.
Officers with both Oakland and San Francisco police say when a suspect resists arrest it can be difficult to apply the carotid restraint properly.
That's why some California police departments do not allow the use of the chokehold or carotid restraint.
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