Police defended their actions during the incident which occurred last Friday at Creekside Elementary School in Milledgeville, Ga.
"Our policy states that any detainee transported to our station in a patrol vehicle is to be handcuffed in the back. There is no age discrimination on that rule," Milledgeville Police Chief Dray Swicord told WMAZ-TV.
The family on Tuesday demanded that the city change its policy, the Associated Press reported, and claimed the girl was shaken up while at the police station.
Johnson was charged with assault and damage to property, WMAZ-TV reported, but she will not have to go to court because of her age.
Johnson's mother, Constance Ruff, says her daughter was suspended until the start of the next school year.
"She has mood swings some days, which all of us have mood swings some days," she told WMAZ-TV. "I guess that was just one of her bad days."
Image: Handcuffs, via Shutterstock.