The videos, from Sept. 4, 2017, allegedly showed Chauvin striking a Black teenager in the head so hard that the boy needed stitches, then allegedly holding the boy down with his knee for nearly 17 minutes, and allegedly ignoring complaints from the boy that he couldn’t breathe.
“Those videos show a far more violent and forceful treatment of this child than Chauvin describes in his report [of the incident],” Matthew Frank, one of the state prosecutors, wrote in a court filing at the time.

After Chauvin's conviction for Floyd murder, DOJ weighs charging him for 2017 incident involving Black teen: Source
Federal investigators probing Derek Chauvin's use of force against George Floyd are also weighing charging him for a 2017 incident involving a Black teen, a source said.