How did the Salem witch trials start

they began during the spring of 1692, after a group of young girls in Salem Village, Massachusetts, claimed to be possessed by the devil and accused several local women of witchcraft

A group of girls pretended that they were under the spell of a witch ... they would pretend to thrash around uncontrollably, except for when the witch was in their presence. Then they would go stock-still. The courthouses would bring "witches" in front of the girls to see if they would go rigid.