MN researchers found less-lethal weapons used in Floyd protests led to serious head, eye injuries

Updated: Jan. 15, 6:40 p.m. | Posted: Jan. 13, 7:28 p.m.

Researchers studying injuries sustained by protesters and bystanders in the Twin Cities following the killing of George Floyd say “less-lethal” projectile weapons like rubber bullets are not appropriate for crowd control. 

University of Minnesota researchers looked at 89 cases of people checking into the hospital after being injured by police during the protests following Floyd’s killing, according to a letter published in the New England Journal of Medicine this week. The people who were injured ranged from 15 to 77 years old. 

While most police policies guide officers to fire weapons like rubber bullets at a person’s body, the researchers found that about 40 percent of people injured by rubber bullets had head injuries, said Erika Kaske, a second-year medical student at the university who worked on the study. 

“This is at a rate that is much higher compared to the current literature,” Kaske said of the head injuries. “In our study, we quote the guidelines and they say that hits to the head and hits to the face are potentially unlawful.” 

The head injuries were also much more serious than previous studies would have predicted, said Dr. David Darrow, an assistant professor of neurosurgery at the University of Minnesota. About 18 percent of the patients had traumatic brain injuries and 11 percent had eye trauma. 

“We were generally surprised by the injuries due to the fact that so many of them were to the head or the face causing blindness or traumatic brain injury or requiring surgery,” Darrow said.

The researchers also looked at people who went to the hospital after being injured by tear gas, chemical irritants like pepper spray and beanbag rounds. They also found that the tear gas canisters themselves accounted for some serious injuries when they hit people. 

Authorities release tear gas Thursday in St. Paul
Authorities release tear gas on May 28, 2020, in St. Paul during protests over the police killing of George Floyd on May 25.
John Minchillo | AP Photo 2020

The researchers only looked at cases where people went to the hospital, which makes it likely many other injuries went undocumented, Kaske said. 

The police response to the insurrection by President Donald Trump’s supporters in the U.S. Capitol building spurred claims that law enforcement responded differently than they did to this summer’s Black Lives Matter protests. Another study published last year by a researcher at York University in Canada found that police responded more aggressively against left-leaning protesters than right-leaning protesters. That study, which hasn’t been peer reviewed, found that ten times as many left-wing protesters were arrested as right-wing.  

The research can help inform the public health impact of law enforcement approaches to protests, said Rachel Hardeman, a professor with the University of Minnesota’s School of Public Health, who also contributed to the research. 

“I certainly hope that this paper is a starting point for people and for law enforcement and our police departments to really be evaluating their use of force and what's actually necessary,” Hardeman said. “I think we have a very real opportunity right now as we consider, again, what safety looks like and what it means in our communities.” 

The researchers plan to continue to study the injuries sustained during demonstrations and said they’re willing to share their findings with law enforcement agencies and others. 

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