The attack by 10 men and six women, who entered their not guilty pleas at the US district court in Ohio, was allegedly motivated by a dispute over church discipline.
Several members of the group, living in Bergholz, were alleged to have forcibly taken shears to the hair of the victims, in September, October and November, and took photos to shame them.
They were in court to respond to an updated indictment, which added new allegations they tried to hide or destroy evidence, including a disposable camera, shears and a bag of hair.
The 10-count indictment includes charges of conspiracy, assault and evidence tampering in what prosecutors described as hate crimes motivated by religious differences.
The alleged ringleader, Samuel Mullet Sr, said in October that he didn’t order the hair-cutting but didn’t stop his sons and others from carrying it out. He said the goal was to send a message to other Amish that they should be ashamed of themselves for the way they were treating Mullet and his community.
Ohio has an estimated Amish population of just under 61,000, second only to Pennsylvania.