Overwhelming scientific evidence has found that restraining an arrestee in the prone position does not create an exceptional risk of serious injury or death.
Yet thanks to allegations leveled by plaintiffs’ attorneys and police critics, the myth of potential harm persists, including the claim that the weight of an officer placing a knee on a suspect’s back to aid in stabilizing and handcuffing can cause “restraint asphyxia,” a supposed fatal impairment of the subject’s ability to breathe.
Now the latest study of prone positioning has debunked that assertion.
This research measured the amount of downward pressure (“weight force”) that’s transferred from an officer to a suspect when the officer temporarily applies one or both knees to a suspect’s back to help maintain control until the cuffed subject can safely be rolled to his side or raised up.
The conclusion: none of four knee-on-back techniques commonly taught and used in law enforcement transfers any amount of weight even close to being dangerous, regardless of how heavy the officer applying the force is.
Believed to be the first of its kind, the study is authored by a six-person research team, headed by Dr. Mark Kroll, an internationally renowned biomedical scientist with the U. of Minnesota and California Polytechnical U. who testifies frequently as an expert witness in police litigation.
“Our findings are important,” Kroll told Force Science News, “because North American officers control and restrain agitated and resistant subjects in the prone position over half a million times each year. Subjects end up being proned out in about 60 per cent of physical force encounters—without a death or serious injury resulting.